First half 2021 NRL advanced statistic leaders

The NRL season has hit the slow period of the season to accomodate for State of Origin, meaning it’s a good time to continue the Eye Test’s review of the first half of the season. Last week we looked at the decline of 80-minute players. This week we’re diving into the advanced statistic leaders for the season up to Round 12.

If you’re unfamiliar with the advanced stats used here at the Eye Test, I’d recommend checking out the glossary page on the site to get up to speed. If you want a longer run down, there are longer posts on Tackle %, Run % and Involvement Rate that talk about how they are calculated and how they should be used.

If you want an even quicker rundown than the Glossary page, here’s the cliff notes. Tackle % and Run % show the % of completed tackles or run made by a player whilst on field, adjusted for minutes played and possession. Involvement Rate combines both Tackle % and Run %, and all three are “work rate” metrics to gauge the contributions of players (typically middle forwards) who don’t play big minutes.

The average rate for each of these metrics can be seen in the chart below. Generally middle forwards (front row, hooker, lock and most interchagne players) make tackles at a rate in the 25% range, have a run rate in the 10-12% range and their Involvement Rate sits between 14-19%. As you move further out to the edges and outside back positions those numbers continue to drop as they are doing less of the grunt work.

One thing worth mentioning is that the Melbourne Storm use a similar metric for “work rate markers”, calculating runs, tackles, supports and kick pressure on a per minute basis. Great minds etc…

Net Points Responsible For (NPRF) is a metric to show the contributions of players beyond the typical try and try assist statistics. And finally, Error Rate is a measurement to identify players who are committing errors more frequently.

For the first three advanced stats, I’ve implemented a minimum of three games played and 120 minutes (playing at least three full halves) to filter out any players with a low sample size. For Net Points Responsible For, I’ve increased the threshold to give games played, as one or two blowouts can skew the data. For Error Rate, the limits are four errors committed and three games played, again to remove any small sample biases.

These statistics are for the first half of the season (Rounds 1-12), and don’t include the recently completed Round 13. And as usual I’m using Fox Sports NRL statistics.

Now the formalities are out of the way, let’s move on to look at the season leaders for the first half of

Tackle % leaders

North Queensland forward Reuben Cotter leads the way with a tackle % of 34.85% in his four games this season. Unfortunately, as he is out for a lengthy period due to Lisfranc surgery and probably won’t make the end of year minute qualification, which is usually between 150-250 minutes played, and is something I gradually increase as the season progresses.

Still his tackle % is almost 10% higher than the average middle forward, with props (25.1%), locks (25.1%), interchange (24.9%) and hookers (25.9%) all sitting in the 25% range, or completing a tackle on one in four possessions.

Coming in behind Cotter is the Sharks interchange forward Billy Magoulias with a tackle rate of 34.0%, followed by promising Tigers middle Alex Seyfarth at 32.74%.

Eye Test first ballot Hall of Famer Daniel Alvaro comes in at 7th with a rate of 30.87%, his seventh season with a tackle rate over 30%, meaning he completes a tackle in three out of every ten opponent plays whilst on the field. Alvaro owns three of the top four end of season tackle rates and can usually be spotted in the top 10-20 players on a weekly basis.

An interesting thing to note is that there are only seven players with a tackle rate of 30% or above. Last season by Round 12 there were 21. In 2019 there were 26. Is this another data point suggesting fatigue is an issue?  

Run % leaders

Penrith’s middle forward machine Spencer Leniu of Penrith takes first place with a run rate of 17.11%, indicating he is completing a run on nearly two out of every five plays for the Panthers. As noted above, the average front rower Run Rate is 12.6%, with Leniu nearly 50% above that number at over 17%.

Leniu was on fire early in the season getting through a huge amount of work in his limited minutes, ranking 1st, 1st, 6th, 80th and 1st in his first five rounds of the season. He’s also the only player with a run rate above 17% this season.

Second place is taken by Roosters prop Jared Warea-Hargreaves at 16.26%, with the Tigers Zane Musgrove rounding out the top three at 15.91%, ahead of former Tiger Josh Aloiai at 15.28%

This year we have seven players with a run rate above 15%, and unlike Tackle % that number is in the same range as 2020 (eight players with 15% or more) and 2019 (five).

Involvement Rate leaders

Given that Involvement Rate is a combination of Tackle % and Run %, it’s no surprise that Reuben Cotter sits at the top of the Involvement Rate chart, with a rate of 22.75%. This means he is either completing a run or tackle on more than one in five plays whilst on the field. The average middle forward has an involvement rate in the 14-19% range, with Cotter sitting at least 3% higher than front rowers and 4% higher than locks.

Second place goes to the Raiders Corey Horsburgh at 22.17%, with that man again Daniel Alvaro snaring third place at 21.96%.

This season there are 20 players with an Involvement Rate of 20% or higher, compared with 29 in 2020 and 48(!) in 2019. To me this is a clear indication that fatigue is having a huge impact on the game.

When looking at 80-minute numbers, the totals and averages may be the same or very similar, which could indicate there’s no change in the speed or pace of the game. However, if fewer players are completing a run or tackle at a high rate, that would indicate that they’re unable to keep up a high workload over the similar periods of time.

Remember that these advanced statistics are not only minute adjusted, but possession adjusted. This means that they are comparable regardless of any raw increase or decrease in minutes played or ball in play.

Net Points Responsible For leaders

Net Points Responsible For (NPRF) is a metric for a player’s overall contribution to a team’s scoring or defense. It is not a measure of overall performance, since it only uses points scored, contributed towards, or allowed. If you do want to put a number on a players overall production, Liam at PythgoNRL has a fantastic overall player performance metric.

Returning to NPRF, this the way it is calculated. Each score by a player is valued as it is on the scoreboard (try – 4, goal – 2, field goal – 1 or 2), plus 4 points for every try assist and try contribution. Four points are removed for every try cause a player concedes as a way of quantifying their defensive contribution. This total is then divided by the number of games played to get a plus or minus total points per game that a player is “responsible” for.

It is a great way of valuing a playmakers influence if they aren’t directly scoring tries or throwing passes that are deemed try assists. By adding in Try Contributions, something like the famed a “hockey assist” (the pass that least to the pass that sets up a score), you can more accurately judge the impact of a player whose involvement may not show up in regular statistics.

With that out of the way, here’s the top players for 2021 thus far.

No one should be surprised with Nathan Cleary topping the list, and at 11.82 NPRF/game, he’s directly adding almost 12 net points per game to the Panthers this season. To put that in perspective, the Bulldogs are averaging just over 11 points scored per game as a team. Given Cleary is touching the ball over 70 times per game, more than any other half in the competition, it’s not surprising his impact on a game is so immense.

Tom Trbojevic is adding +10.29 NPRF/game for the Sea Eagles this season, and his mere presence on the field has turned them from wooden spoon contenders to a legitimate finals football team.

Third and fourth places are taken by a pair of Storm fullbacks, Ryan Papenhuyzen (+8.67) and Nicho Hynes (+7.60). The Storm have four players inside the top 10, with Harry Grant (+6.4) and Jahrome Hughes (+6.18) also having strong seasons.

It’s also worth noting just how good Brett Morris was playing this season at 34, with the fifth best NPRF average this season. The Eye Test would like to wish him the best in retirement, he will be missed.

This chart also indicates how important defense is. Cody Walker is having a great season with the ball, scoring nine tries, handing out 11 try assists and contributing seven more, playing him second in the NRL for total try involvements. But with 11 try causes for the season (meaning he was deemed responsible for conceding a try) his NPRF per game is only +5.89. Without those try causes his points responsible for would be +9.81 per game, well inside the top five.

Error Rate leaders

The last advanced statistic we’re looking at this week is Error Rate, which is the number of possessions it takes for a player to commit an error. As a rough guide, anything less than 10 is terrible, and between 10-15 is bad, and 15-30 is not good.

Dragons winger Jordan Pereira takes top (or should that be bottom?) spot with an error every seven possessions in his three games. That equates to nearly three errors per 80 minutes, which you don’t need me to tell you is not good.

Second place is Warriors backrower Josh Curran, who is committing an error every 9.14 possessions, with Titans edge Beau Fermor at 9.33 making up the top three. Canberra veteran Jarrod Croker is the only other player with an Error Rate under 10 at 9.86.

Pereira is unlucky that I haven’t set the minimum games played threshold for Error Rate at two games played, as Wests Tigers winger Zac Cinto has committed seven errors in just 34 possessions this season for a rate of one error every 4.86 possessions. But as he has only played the two games, he’s currently excluded from this list.

On the positive side of things, Jayden Brailey has the best error rate in the NRL, with just one error in 1,419 possessions. Given hookers are usually just moving the ball from dummy half 150 times a game, it’s understandable they’re not committing too many mistakes.

A special shout out goes to NRL Physio’s favourite and grilled chicken connoisseur Alex Twal, who has played 653 minutes this season, touched the ball 171 times and is yet to commit an error. He’s the only player with at least 500 minutes played yet to commit one.  

The decline of 80 minute players – NRL Round 12 2021 stats and trends

The first half of the 2021 NRL season is over already. Time sure does fly, unless you’re a Raiders fan, and then it probably doesn’t move quick enough. With the passing of the midpoint, it’s time to look back at what has transpired and see what has changed thus far.

Fatigue has been the main talking point this season, with the NRL claiming there is no link between the rule changes and fatigue. I figured it was a good time to take a broader look at how fatigue and injuries has changed minutes played and players used in 2021.

Earlier this season the Eye Test already looked at how teams were using their interchange bench more often, and earlier in games. With fewer stoppages, greater fatigue impact and more line-up changes, it is no surprise that teams who excel in recruiting outside of their own back yard or prioritise developing their own juniors are excelling this season.

Let’s start by looking at a simple measure – the average minutes played by an NRL player.

Over the past eight seasons players about 61 minutes per game, with 2021 sporting the lowest average at 61.12 minutes, beating the previous low in 2014 of 61.32. This makes sense with the number of injuries and head impact assessments, as players who would usually be playing big minutes are spending more time off field.

Notice the average minutes played hasn’t changed much from 2020 to 2021? It’s down but only by a small margin. Keep this in mind for later.

If you look at the change in minutes played by position, you can see why the minutes played has dropped but hasn’t altered significantly.

Most starting forwards are playing fewer minutes, with front rowers, second rowers and locks all playing around 3% less than last season. This has been made up by interchange players, who are spending 5% more time on field, which makes sense given the number of injuries and reduction in stoppages.

The decline in mintues makes sense, given that there has been a high number of players injured and undergoing a HIA most likely due to the reduction in stoppages from poorly thought out rule changes.

Which raises the question, has that affected how many players each team has used this season? The number of unique players used each season is below. For comparison purposes, 18th men have been excluded.

Here we can see some of the affect of the “fewer stoppages” era of the NRL. 2014 was the only time in the previous eight seasons where over 400 unique players had stepped onto a field in the first twelve rounds. The jump from 2019 (397) to 2020 (420) was about a 6% increase. For those who like to claim that there isn’t enough talent to support a 17th or 18th team, we’re using an extra team of players each season due to attrition under the current environment.

Next up I’ve split this out by team for 2021, to understand which teams have coped the best with the increased fatigue, and who has struggled.

No surprises that Penrith and Parramatta have been the least affected by line up changes this season. Those at with the most changes have been brought about by injuries (Roosters, Warriors), suspensions (St George), reshuffles (North Queensland) or a combination of all three (Brisbane, Canterbury).

Moving back to the unique players used, those 423 unique players have played 3,255 games. Of those games, 1,533 players have played at least 80 minutes, or about 47%. How does that stack up historically?

Unsurprisingly, again it’s the lowest percentage of players playing 80 minutes since 2014, and nearly a 2% drop from 2020 when set restarts were implemented in Round 3. Coaches are finding they cannot leave players on the field as long as they used to, whether that be due to injury or fatigue leading to bad decisions. Keep in mind that some players are being forced to play 80 minutes because there were no available interchange players due to injury.

Even more alarmingly, backs (numbers 1-7) are playing the lowest percentage of full games since 2014 as well, at just under 89% of players hitting 80 minutes.

After only once hitting 8% prior to 2020, we’ve had two seasons of the percentage of backs not playing 80 minutes above 11%. Over one in ten backs are now not playing the full game. Regardless of the reason, whether it be concussion, injury or getting hooked, backs are playing fewer minutes than previous seasons.

The last thing I’m going to check is the distribution of minutes played to check for any trends. Below is a box and whisker plot, which can be used to show the spread and a five number summary of a set of data. The numbers are the minimum, first quartile (25%), median, third quartile (75%) and maximum. Here’s how the distribution of mintues over the last eight seasons looks.

The thing that stands out from looking at minutes is that the median (middle number in a set of data) is considerably lower in 2021 than 2020, or any other year in this set. Last year the median was 77, meaning that half of the all players up to Round 12 played at least 77 minutes. This season, it’s down to just 71 minutes, which is almost a 10% change in one season. Yet as I mentioned before the average was similar (61.39 in 2020 to 61.12 in 2021).

The third quartile hasn’t changed much, and at 41 minutes is in line with other seasons, confirming what we discovered earlier, that fewer players are playing the full 80 minutes and it’s dragging down the median. Those minutes are being distributed to interchange players who are spending more time on field and the average is masking the change. It’s also why you don’t use averages in your press releases to unsuccessfully quell player unrest.

It’s pretty hard to argue now that players aren’t being affected by fatigue this season, with fewer playing 80 minutes, interchange player are spending more time on the field and a larger percentage of backs aren’t playing the full game.

The NRL can use whatever unrelated metrics they like to show that things are working. but as a wise man once said, “the kind of people swayed by statistics are generally not swayed by bad statistics and have keen enough noses to smell dumb shit a mile off”.

Being concerned about player welfare and not being a fan of the current rules aren’t mutually exclusive. Unlike those with a predisposed agenda, the Eye Test is agnostic and only relies on facts.

Net post contact metres

Post contact metres are often used as a barometer for success for NRL teams, as run metres correlates highly with winning games. But how do you judge if a team won that battle? Gaining 600 metres post contact sounds good, unless you’re giving up 700m.

The answer is to look at their net post contact metres. Net post contact metres is derived by taking a team’s post contact metres and subtracting their opponents post contact metres.

The chart below shows all 16 NRL clubs and their net post contact metres over the twelve rounds played this season, with a line showing their average net post contact metres for 2021.

There are a few reasons I like this chart, which I used last season as well. The first is that I can see every team at once. The second is that it clearly shows who is performing well (Penrith, Melbourne), and who is struggling.

Canterbury haven’t had a game with positive net post contact metres all season and are giving up an average of 180 more to their opponents. Melbourne, on the other hand have only lost one post contact metre battle all season, which came in Round 7 against the Warriors in a game they won.

The third is that it’s great at showing the ebbs and flows of a team over a period of time. Parramatta’s success over the past two months can be seen before screeching to a halt in the last two rounds against Manly and South Sydney. The Raiders struggles can be seen as well, coming out on top only a handful of times.

It also shows that despite the Dragons strong start to the season wasn’t sustainable as they didn’t win a single post contact metre battle during that time. They have only come out on top once this season, which was Round 9 against the Bulldogs, who everyone comes out on top against.

To’o’s rise to Origin

The naming of Panthers winger to the New South Wales State of Origin team this week ruffled a few feathers, with detractors pointing to his lack of heigh compared to Daniel Tupou as a liability at that level of the game.

It may be the case, but if you compare the two players statistically this season there’s no doubt To’o is ahead of Tupou but not by a wide margin. Tries per game is the one metric where the Roosters winger comes out ahead.

The main difference is the incredible work rate and damage To’o does when running the ball. I’ve posted the next two charts a number of times but given his selection it’s worth revisiting them.

To’o is still blitzing the rest of the league in long runs (greater than 8 metres), with 16.6 per game. That’s almost as many total runs per game as Tupou has (18.2).

He’s also busting nearly twice as many tackles as Tupou as seen below.

With the fast past of State of Origin set to be even faster this season with the new rule changes, having someone with the work rate and explosive ability holding the ball that To’o has could be an important factor in spelling the Blues back when they’re gassed.

Are the Raiders’ second half struggles the worst in the NRL? Round 11 2021 stats and trends

We all know the Raiders have had some shocking second halves this season, and Round 11 was no different.

It’s been documented a number of times and it’s not any ground I’m going to attempt to cover. The Raiders are very, very bad in the second half, I can’t provide any new information here. This article on NRL.com goes into great detail of the changes in the Raiders stats after half time.

What I am going to look at is how their second half struggles compare to the rest of the league to see if there’s anything that stands out. Are they the only team having bad second halves or are there other teams suffering alongside them from the 41st minute onward?

To start, let’s look at the average margin by half and NRL team for 2021 after 11 Rounds. Quick reminder that I’m using Fox Sports stats which will have a very minor difference to the official NRL statistics.

The chart is below – green dot represents first half margin, red dot represents second half margin and the line between shows the size of the gap. The chart is sorted by second half margin (red dots).

As you’d expect it’s not a pretty sight for the green machine. They are next to last in average second half margin at -10.5, over fifteen points fewer than their first half margin. You can also see by the size of the bar between the red and green data points that it is the largest gap between halves this season, over double that of the next worst second half performer, the Gold Coast, at a difference of -7.2.

How does that rate in context of recent seasons? The worst second half margins since 2014 are in the chart below.

The previous worst second half teams by margin were the 2015 and 2017 Warriors. The Raiders are on track to beat that record handily. The Titans should be very happy the Raiders exist because otherwise we’d be talking about their second half capitulations instead.

Slightly concerning is the fact that that the worst two sides are from this season. It’s another data point highlighting the increasing inequality that rule changes in 2021 have caused.

Moving back to the 2021 chart, North Queensland might be faring a bit better on the ladder if they weren’t giving up so many first half leads, as they sport the biggest increase from first to second half margin. It should also surprise no one that Melbourne and Penrith are the top two teams in either half and their margin barely differs.

But back to the Raiders, let’s delve into some more statistics to see where they sit and try to get an understanding of just why their second halves are so putrid. First up is run metres by team.

Another woeful chart for Canberra, going from third overall for first half metres to dead last in the second half. Again the largest gap between points. And if you flip things around and look at teams playing the Raiders, it’s a similar story.

Second most metres given up in second halves, only ahead of the tragic Bulldogs. The sorting of this chart somewhat reflects the NRL ladder just inverted, with the top 5 giving up the fewest run metres per second halves. Again it would indicate the Cowboys could be playing in September if they sorted out the start of games.

Let’s move on to metres per run and see if Canberra is giving up more metres per carry in the second half.

They are, but not to the extent of other teams, at just an extra 0.3m per run. The Sharks fare the worst here, giving up an extra 0.7 metres per run after half time. If you flip the data to look at opponents, teams playing Canberra sit around mid-table.

The increase is smaller, from 8.9 to 9.1 but it’s still there although not as concerning as it would be for teams like Newcastle and Cronulla, who can’t hold on to attackers after the break.

There’s not a lot of change if you look at metres per set. Most teams in the NRL gain more metres per set in the second half, but the Raiders sit fourth from the bottom and have one of the smallest changes from first half to second half.

Flipping that chart to look at data by opponent tells the same tale, with Canberra sitting in the wrong half of the ladder and conceding more metres per set than in the first forty minutes, almost four extra metres per set, on par with Newcastle and St George and only ahead of Canterbury.

I’m sure you’re getting the idea now. The Raiders are giving up significantly more metres in second periods and can’t generate it themselves. The bigger issue is their inability to maintain possession and hold onto the ball, making them by far the worst performing club in the NRL for second halves. This last chart summarises their plight well, and it’s all about possession and their inability to complete sets.

After only trailing Penrith in first half complete sets at 17 per game, the Raiders drop to dead last in complete sets in the second stanza at under 13 per game. Penrith and Melbourne also suffer declines in complete sets, but they’re still in the top half of the competition for that stat in the second half.

You might argue that I’ve stated that complete sets don’t matter, to which I’d reply you’re half right. Completion rates don’t matter, but complete sets do. 90% of 10 is nine, but 70% of 20 is 14. If you can’t control the ball and field position (something I covered last week), you are always going to struggle.

The Raiders second half struggles are mainly due to their inability to hold the ball, and they can’t compete against the increased possession. If it continues at this rate then they will be crowned the worst second half team in the NRL since 2014.

Are teams throwing the ball around more this season?

In looking into the Raiders struggles at holding the ball, I started looking into how often teams were passing and offloading this season compared to previous seasons. It turns out the rate of passing is up but very slightly but still below previous years compared to the same point in previous seasons.

The NRL average this season is 0.66 general passes per play the ball. That number doesn’t include dummy half passes, so just add a 1 in front for total passes. Still, that rate is down on 2018 and 2019 as you can see below.   

Offloads per play the ball are following the same trend of peaking in 2018 and dropping until a slight uptick this season to just over 0.06 per play the ball.

Given this increase, which teams are driving the changes? Here’ how the sixteen NRL clubs rank using the same rate of general play passes per play the ball.

Penrith take top spot with 0.77 passes per play the ball (remember to add +1 for total passes), slightly ahead of Cronulla and the Roosters. At the other end of the scale is North Queensland, passing just 0.49 times per play the ball.

Switching it to an opponent view below, there’s two things that stand out.

The first is that to no one’s surprise, Penrith and Parramatta allow the lowest pass rate against them this season, although there isn’t much separating second through thirteenth. It appears as if teams are playing extremely cautiously against the Eels and Panthers, with more one out running and trying to play mistake free.

The second part that is probably more surprising is Melbourne allowing 0.76 passes, by far the most in the NRL. Teams either believe they need to move the ball more to unsettle Melbourne’s defensive line, or the Storm are giving them opportunities to do so and are backing their defense.

The year on year change for offload rate tells another story.

Penrith have focused strongly on promoting the ball and are offloading at a rate 52% higher than last season. And North Queensland have tucked the ball away under Todd Payten, with 17% fewer passes, despite their coach letting the Warriors off the leash last season to promote second phase play, which the Eye Test picked up early on.

Bringing this together, how does it look when you compare passing rates to offload rates? Are teams that throw the ball around also likely to offload more? To check I’ve plotted both passing and offload rates for each club and broken them down into expansive and basic passing, and high and low second phase play. The size of each data point represents total margin for the season to show if it’s successful. Whether or not more passing is expansive or not is an assumption I’m making, and it may not reflect reality, but generally more passes indicates spreading the ball. Anyway here are the results.

Most of the top eight sides sit in the “Expansive & high second phase play” quadrant, with six of the current top eight dwelling here, indicating that if you’re willing to distribute the ball more and are able to offload then you’re most likely sitting among the more successful clubs. Or it may be that these clubs are the best at exploiting tired defenses and are pushing the ball wider and faster when they have an advantage.

Cronulla sit alone as a team that passes the ball regularly but doesn’t offload at a high rate, while the Warriors, Knights and Broncos all aim to promote second phase play but spread the ball less than the NRL average.

The bottom right quadrant with a basic passing game and low offload rates contains the safe and cautious approaches, which isn’t overly surprising that it is where Wayne Bennett’s Rabbitohs are placed. The risk adverse Bulldogs also reside here (I assure you that’s a data point and not a mark your screen), as do the Dragons and struggling Raiders.

Again, the Cowboys are an anomaly this year, playing an extremely safe brand of rugby league which goes against the free flowing attacking style of football that Payten encouraged at the Warriors last season. It’s a sign of a good coach that he’s modified his style to suit his players, and if it weren’t for some bad opening losses and giving up early leads they’d be firmly entrenched inside the top eight.

Error rate

As mentioned above the Raiders have had a terrible time holding the ball this season, and it shows when you look at individual error rates.

South’s Jed Cartwright sits in first place with three errors in just sixteen possessions, for a rate of one error every 5.33 touches. He’s followed by a pair of Warriors, Jack Murchie at 9.0 and Josh Curran at 9.14.

Next up is Raiders centre Jarrod Croker, who has committed 7 errors at a rate of one every 9.86 possessions. Four other Raiders also feature inside the Top 30, with three of them – Hudson Young, Elliott Whitehead and Jordan Rapana – sporting errors rates lower than 15 and raw error totals in double digits. Meaning not only are the Raiders committing errors at a higher rate, but they’re also being committed by players who touch the ball more frequently. A surefire recipe for disaster.

Tigers cult hero Zac Cini would actually top the chart with 7 errors this season from 34 touches, for a rate of 4.86. Unfortunately, or fortunately if you value the ball, he’s only played the two games and doesn’t meet the games played threshold.

Field position is the new NRL currency and the top three are dominating it – NRL Round 10 stats and trends

Nothing like a quiet week in rugby league.

Magic round has come and gone, and the game is further slipping into territory that could be best described with the “f” word – farce. The blowouts have continued as well, as shown by the wonderful charts from friends of the site NRLFanalytics and AndrewRLP at the conclusion of Round 10.

It was only four seasons ago that we had almost 40% of games decided by one score. Now it is almost half of that, with just 21% of this seasons 80 games decided by 6 points or fewer.

We know that the changes in rules are contributing to these scores, with the top teams exploiting their advantages in a number of ways. One way is by controlling field position at a rate that hasn’t been seen in years.

With rules designed to encourage fewer stoppages and increase time in play, we’ve seen more of the game played through the middle of the field with teams are running out of their own half more. In the era of penalties instead of set restarts, teams would spend more time in midfield as they’d get a free 20-30 metres of field position.

A few rounds back I showed the below chart, which breaks down the percentage of play the balls into three locations – inside own half, opponents’ midfield, and opponents 20m zone. I find it’s a great way of showing if there’s been any movement in where the game is being played, and over the past few seasons it has moved after a stable period from 2014-2017.

The percentage of play the balls inside a team’s own half has increased from 51% in 2018 (coincidentally the last “crackdown”) to 57% in 2021. Here’s the update after Round 10 and things haven’t changed much since the last update.

It also shows that most of this own half possession is coming at the expense of time spent in an opponents 20m zone, which dropped under 20% in 2020 and is down to just 18% this season. That’s not necessarily a bad thing, as you don’t need to spend time inside the 20 metre area to score a try, which is one of the great things about our game. But it does point to safer football being played outside attacking areas.

I alluded to it earlier, but part of this is the contenders being able to dictate field position a lot easier with a miniscule punishment for slowing down the ruck or creeping offside. Here’s the breakdown if the above chart by team for 2021.

Penrith stands out here with only half of their play the balls coming from inside their own end of the field. Anyone who has been watching them play over the past two seasons knows it is a part of their game, and was something that the Eye Test noticed last season. North Queensland are next at 52% and have historically had a low own half percentage due to Jason Taumalolo picking up 10 metres every time he runs the ball.

At the top of the scale, the Dragons spend over 63% of their play the balls inside their own half, and just 14.6% inside their opponents 20 metre area. The Tigers spend the most time inside an opponent’s 20 metre area, with 23.4% of their play the balls coming from that part of the field but haven’t been able to capitalize as they sit ninth (cue laughter) in points scored.

Unfortunately, that chart doesn’t really convey the point I’m trying to make though, as Melbourne spend the fifth most time inside their own half at nearly 60% yet have the second best points differential in the NRL.

Where you do see it is when you change the perspective to opponents, as shown below.

The top three this season, Penrith, Parramatta, and Melbourne, are all keeping opponents inside their own half on at least 62% of play the balls and restricting them to 15% or fewer play the balls inside 20. Parramatta specifically are holding teams in their own half for nearly two thirds of total play the balls.

To put this in perspective, there has only been one team since 2014 that has held opponents to 60% of play the balls in their own half (we’ll get into that shortly). This season we have three. It’s yet another data point showing that the new rules of rugby league are contributing to some incredibly one sided results.

Souths aren’t too far behind the top three at 59.5%, while the Roosters buck the trend of the “big 5” teams for 2021, at nearly 10% lower than the top three, with just 53% of their opponent play the balls in their own half. This isn’t too surprising, because as discussed a few weeks ago, the Roosters usually have one of the worst completion rates in the NRL and regularly give up field position to opponents, relying on their strength in defense.

Another noteworthy point from this version is that Wests Tigers opponents spend the third most amount of time in their 20 metre area. If you combine that with the amount of time the Tigers spent attacking the try line, it would appear most of their games are played at either end of the field and much less than an average NRL game spent in between. Which probably explains their dysfunctional start to the season.

Staunch supporters of the NRL regime will claim that “there have always been teams blowing out other teams” I hear you say. And you’re right. But none of them are doing so with the vice like grip on field position that the Storm, Eels and Panthers are this season.

The chart below shows average margin of teams by opponent and season, plotted against the amount of time spent in their own half by percentage of play the balls from 2014 to 2021. Data points are coloured by season, with yellow representing 2021.

Here it’s even more obvious just how much of their performance this season are outliers and that the new rules are playing into this. As I alluded to earlier, only one other team has held opponents to more than 60% of play the balls in their own half since 2014, which was Penrith in 2020 (the green dot just below the Panthers 2021 data point).

The NRL average from 2014-2021 is 54% of play the balls in your own half, and every team this season other than the Roosters (who we identified above at 53%) are above this long term average. This chart also shows just how the 2021 average of 57.4% is skewed by the top three teams. Additionally, no other teams have been averaging more than 15-point margins of victory during this period either.

This trend towards controlling field position is even more apparent when you break these numbers down to halves, showing the Eels have a stunning command of field position in second halves.

Teams facing Parramatta spend almost 70% of their time in their own half, with less than 10% inside the Eels 20 metre zone.

The blowouts will continue as long as the rules benefit those who flaunt them the most, expanding the gap between the very good and the very ordinary.

Let’s try that crackdown again

Looks like I was a bit premature in suggesting the crackdown wasn’t a crackdown last week, with 23 charges and a slew of penalties last weekend. The full rap sheet is below:

There were 86 penalties in Round 10, 10.8 per game, up from 60 in Round 9, and the most since Round 5 2020 when teams worked out how to game set restarts. That’s still a far cry away from the 16 per game we saw in the height of the penalty crackdown of 2018, but still a significant increase. If the NRL wanted to deliver a message about high shots, they certainly achieved that.

Unsurprisingly, when you combine that increase with the number of tries scored, Round 10 saw the lowest time in play since Round 13, 2019, coming in at 52.97 minutes. That’s the first time since the introduction of set restarts that time in play has dropped under 53 minutes.

Below you can see the relationship between tries scored and time in play. Generally the trend is that the more points scored, the lower time in play.

The other thing of note with this crackdown is that there was very little change in set restarts being called. In Round 10 there was slight increase in first halves (3.9 to 5.0), and an identical number in second halves (3.1). Below is the half breakdowns of set restarts and penalties awarded where you can see just how little changed with set restarts.

The big difference came in penalties awarded, jumping from 3.88 to 5.0 in the first half and nearly two whole penalties more blown in second halves, up from 3.63 to 5.75.

Part of that was due to two games – Tigers v Knight and Penrith v Titans – having a total of 17 penalties awarded in each game. Here’s the Round 10 split by timeslot.

Only one other match was in double digits, which was Friday evenings Brisbane v Manly game, and every other match had fewer than 10 penalties awarded. If you remove those 17 penalty outliers, the round average would be 8.6 and much closer to the season average.

It will be interesting to see how long this crackdown lasts, as mentioned above the 2018 didn’t last past the midpoint of the season. This one affects player welfare which is why I hope it does continue, even if it was atrociously implemented with little foresight just like the rest of the rules under our esteemed emperor.

I probably can’t sum it up much better than the tweet from my personal account on Friday evening at the conclusion of the Broncos/Sea Eagles game.

The main issue is that the root cause of these high shots isn’t being adressed by this crackdown. Someone in power will need to admit they were wrong by removing stoppages which have led to this situation. If player welfare is the main issue, then the logical conclusion would be to stop forcing them to compete under extreme fatigue which is exacerbating these issues.

What the Eye Test and Melbourne have in common

Overshadowed by the goings on in the Brisbane v Manly game was an article by Roy Masters on the Sydney Morning Herald site on Friday evening. The headline was a bit misleading, but there was some excellent insight in the article regarding the pace of the game.

Most of it will be common ground for regular Eye Test readers, but my favourite saying about analytics and data is that it is the “art of being less wrong”. The article is still worth a read, however, as it brings up some new data points and insights.

One of the new nuggets of information that I did find extremely interesting is that the Storm look at “work rate markers”:

“For example, the Storm calculate what they term “work rate markers”, counting a player’s total runs, tackles, support, and kick pressure, divided by the number of minutes the player is on the field.

Whenever former champion fullback Billy Slater recorded a score of 0.22, he walked off the field totally spent, while this year’s custodians, Ryan Papenhuyzen and Nicho Hynes, have averaged figures 30 percent higher than Slater.”

Demise of the robots: Why ad-lib football is king again, https://www.smh.com.au/sport/nrl/demise-of-the-robots-why-ad-lib-football-is-king-again-20210514-p57ry0.html

Regular Eye Test readers may know that the site was founded on needing somewhere to provide some context for the advanced stats I use – Tackle %, Run % and Involvement Rate. These were liberally cribbed from NBA advanced stats and I tried to apply similar thinking to rugby league. The aim was develop something that would show workrate but not favour those who played more minutes and filled up more statistical buckets, as the VB Hard Work index does.

I’d started calculating them sometime in late 2018 as a way to identify middle forwards work rate, which highlighted how big a motor Eye Test first ballot Hall of Famer Daniel Alvaro has. Below is the first time I could find that I posted them publicly, well before I had even thought about the Eye Test.

The largest difference between my advanced statistics and what the Storm are using is that I also adjust for possession, rather than just doing a pure per minute rate. If two players made 50 tackles in 80 minutes, but Player A faced 150 play the balls and Player B faced 100 play the balls, the second player is making the same amount of tackles at a higher rate. It’s a minor change that doesn’t penalise players who face a lower number of play the balls, since you can’t complete a tackle if your opponent doesn’t have the ball.

Back to the article, seeing that Melbourne is using something similar prompted me to check how some of my advanced stats compared to the Storm example in the above article. Was there a corresponding increase for Papenhuyzen and Hynes? I’ve used Run % as fullbacks don’t make a large number of tackles and I don’t have access to data for decoys or kick pressure, but the results for every Melbourne fullback that has played at least two games since 2014 are below.

Slater owns four of the bottom eight results for the 17 fullbacks Melbourne have used since 2014 who have played at least two games. In seasons where Slater played more than seven games, his Run % was in the 8% range. You can see that Papenhuyzen, Hynes (in 2020) and Munster, all have a Run % higher than 10%, with Papenhuyzen at 10.62% for 2021, which is slightly under 30% higher than Slater’s peak. Even for 2021 Hynes is still ahead of Slater’s best season during this period. That does show that Melbourne fullbacks are getting invovled more in recent years than during Slater’s era.

Apologies for the navel gazing, but I felt it’s worth pointing out that someone with very limited time due to full time work and family commitments independently came up with a similar internal metric to used at an NRL club, using only publicly available data. Imagine what the wider NRL community could come up with and advanced the acceptance of data within the game if more information was easily accessible?

What was the result of the set restart “crackdown”? – NRL Round 9 20201 stats and trends

Last week the NRL noted that there would be a “crackdown” on deliberate infringements on early tackles that lead to set restarts, as it has become more obvious that teams are gaming them for reasons that myself and many others have mentioned before. Basically, it comes down to field position, as giving away one or two extra tackles is far outweighed by conceding an extra 20-30 metres down field as well as a fresh set of six.

What was the result of this set restart “crackdown”? Fewer penalties than Round 8 and slightly more set restarts. Not a lot of changes at first glance.

When you look at them broken down by half, a few variations can be seen. Penalties in the first half were identical to Round 8 and right near the year-to-date average. Second half penalties though were down by nearly one full penalty, and the lowest since Round 4.

Where it gets interesting is that first half set restarts were also down, at just 4.5 per first 40 minutes, also the lowest since Round 4. Not only did we have fewer penalties, but we also had fewer set restarts in the opening period. As mentioned before second half penalties were down by nearly 1.0, which looks to be offset but the increase in second half resets of 1.0, which makes perfect sense. Infractions that were being called penalties in previous rounds were being given as set restarts.

Back to the first half decrease, there are a number of reasons this could be happening, ranging from teams being wary of the crackdown and behaving themselves (unlikely) and referees not calling as many first half restarts (more likely). As mentioned every week, I’m just using publicly available data, and the larger dataset the NRL and clubs have may show something about which tackles restarts were being conceded on, but for now this is the best we can use for analysis.

There’s also the number of one side games resulting in less ball in play, since you can’t concede a penalty or set restart if watching someone take a conversion. It doesn’t look like that had an affect as the rate of these violations being called was constant with previous rounds.

One of the other metrics I look at to gauge how they’re occuring is the number of play the balls per total infringement. Below is that metric broken down by halves.

Overall, it’s about one penalty or set restart every 20 play the balls, or roughly once every three sets of six. Round 9 was one every 18.8 play the balls, right around the average. And by half it was about the same as well – right on the first half average of 18 and slightly under the second half average of 23.

In the end it seems like the set restart “crackdown” this week was a bit of a nothingburger. It was significantly overshadowed by the NRL’s unsafe working environment, which is something that absolutely needs a “crackdown”.

Team breakdown of set restarts and penalties

One of the more common requests I get through the Eye Test social media accounts is which teams are giving up or receiving the most set restarts. The reason for this seems to be that the NRL and Fox Sports (which I use as they’re the NRL Supercoach currency) don’t have them included on either of the stats pages. That’s not overly surprising as it took about six rounds for the NRL to even include them on their match stats pages.

Moving on, here’s the breakdown of set restarts awarded by team for the first nine rounds of the competition, split by halves. First halves are in blue, second halves are in orange with a total number at the end of each row.

The Wests Tigers have had the most set restarts go their way this season, with 44 in their nine games this season, just ahead of a trio on 41 (South Sydney, Parramatta, and Canterbury). Across the league there’s a pretty constant trend of teams receiving more set restarts in the first half than second half, with the notable exception being the Bulldogs who are the only club to receive more than 20 restarts in the second half this season.

Flipping things around, who are the worst teams at conceding set restarts?

It’s a landslide here with the hapless Bulldogs conceding 51 set restarts this season, eight ahead of second placed Melbourne with 43. In fact, the Dogs have conceded more first half set restarts (40) than the total restarts conceded of all but one other NRL club.

Let’s move on to the same charts for penalties awarded and conceded.

South Sydney have been by far the biggest beneficiary of penalties this season, with 50 in their nine games, 11 more than the next closest teams (Manly and Wests Tigers). Souths have had more second half penalties awarded (26) than Brisbane have had all season (24), which a considerable amount of extra possession for the Bunnies.

Now on to penalties conceded by team this season.

The Titans, Bulldogs and Roosters leading the way, all with more than 40 penalties conceded this season. Newcastle is by far the most disciplined team in this regard, giving up only 22 total penalties and just six in the second half, fewer than one per game. No other team has a half in single figures.

Now we’ve established who is benefiting and suffering from these infringements, let’s look and see how it relates to winning, which is why the games are played. Before we look at 2021, it is worth checking where things were last season. Below is a chart of net set restarts (awarded minus conceded) plotted against net margin for Rounds 3-9 2020.

Last season at this time, Penrith had conceded 23 more set restarts than they were awarded, which obviously worked for them. And it’s a great reminder for those who believe that this gaming of set restarts might be a new thing in 2021, it isn’t’. After just seven rounds of set restarts purely for ruck infringements in 2020, it was pretty clear that the top four sides at the time (Penrith, Sydney, Melbourne, and Parramatta) had worked out how to game them.

If we look at things for the 2021 season, with more infringements able to be called for a set restart, things are quite different. Here’s the same chart as above for 2021.

Melbourne are the Panthers of season 2021, conceding 14 more restarts than they’ve been awarded. The Roosters are the only other team in that “conceding and winning” quadrant. They’re both still using set restarts as a way to manage field position, confident in their defense to hold opponents out.

The other significant change is that the remaining major contenders for this season aren’t conceding more set restarts than they’re awarded, with Parramatta +5, Penrith +7, and Souths +11. These teams are looking more at maintaining position and pushing the ball through the middle and not letting opponents get settled defensively.

The rest of the competition can be grouped mostly into the other two quadrants, “conceding and losing”, containing the Bulldogs and slow starters like the Cowboys and Sea Eagles, and the “not conceding and losing” quadrant, which has most of the mid ladder teams who’ve given up a big score to one or more of the top five sides.

The last thing I wanted to look at was if there was any relationship between net set restarts and net penalties. Do teams only concede set restarts? As you might expect, there is some relationship.

Teams that generally concede more set restarts than they’re awarded also concede more penalties. The Roosters are -5 on set restarts and -13 on penalties, whilst Melbourne are -14 on set restarts and -1 on penalties. As we saw before, Souths are +11 on set restarts, but they’re also a whopping +20 on penalties. Manly is the only real outlier in this view, sitting at -7 on set restarts and +13 on penalties.

It’s not as clear cut this season that managing your restart counts is helping contending teams, but it’s still a case that possession and field position are as important as ever.

Matt Dufty tightening up his defense

The Dragons are currently sitting in sixth place on the ladder, and Matt Dufty has been one their keys as you would expect. He’s been as elusive as always with the ball, but it’s the other side of the game that has impressed me this season.

In 2020 Dufty gave up 21 try causes in 18 games, around 1.2 per game. Thus far he has just six in 9 games, around 0.7 per game. When you combine try causes with line break causes, in 2020 he was in the 54th percentile of all outside backs, meaning that 46% of all outside backs gave up fewer line breaks and tries than Dufty. Not exactly the sort of defensive effort you’d expect from a starting fullback on a team with top eight aspirations.

In 2021 that percentile rank has crept up to the 73rd percentile, which still isn’t in the elite tier but still an impressive improvement to go from sitting in the middle of the NRL to almost top quarter. Dufty’s percentile ranks this season compare favorably with James Tedesco, who may not be having his best season behind a crippled Roosters pack, but he’s still one of the biggest gamebreakers in the competition.

Dufty has always been one of the better attacking fullbacks but his defensive lapses were always a talking point. If this improvement continues, he could be on the heels of the big four NSW fullbacks.