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A lot happened in North London on Saturday.
For starters, Arsenal won, 2-1, against West Ham United. Granit Xhaka passed the ball forward 660 yards. Arsenal, as a team, advanced the ball 3,025 yards as a team. Pierre-Emerick Aubameyang created four shots. Dani Ceballos and Alexandre Lacazette each pressured an opponent 19 separate times. Bukayo Saka had four passes blocked and created two goals. Gabriel cleared the ball nine times and touched it 14 times in his own penalty area. Bernd Leno only played the ball long on one of his five goal kicks, and he came out of his box to complete a defensive action twice.
We, the non-proprietary public, are getting better and better counting the things that happen on a soccer field. Of course, even the ability to count nutmegs and successful pressures and passes played off the ground but also below shoulder height still misses most of what’s happening on a soccer field: all the stuff that exists beyond the players on the ball. But advanced tracking data isn’t really necessary to understand what’s going at Arsenal, and neither is more detailed on-ball info.
Since Mikel Arteta was hired by Arsenal back in December, they’ve won some trophies, they’ve taken scalps off two of the best teams in the world, and they’re a perfect six-points-from-six through two games so far this season. They seem like they’re headed in the right direction, but they’re not going anywhere until they figure out how to shoot -- and to stop their opponents from doing the same.
It might sound silly now, but the shot was the foundational metric of the fledgling analytics movement from early last decade. Players that created a lot of shots: good! Players that took a lot of shots: even better! Teams that took a bunch of shots and allowed only a little: the best!
“[Shot data] was the building block to get from scorelines to xG,” said James Yorke, Head of Analysis at the consultancy Statsbomb and himself an influential early blogger. “Without shot stuff, there is no xG.”
Much of that shot stuff was put forth by the analyst James Grayson on his blog, which was literally called “James’ Blog”. First, he looked into the correlation between points and total shots ratio -- the percentage of the shots a team attempts in their matches. Here’s what he found, back in the summer of 2012:
And here’s what he wrote at the time:
There’s a pretty clear pattern here – those teams that control less of the ball (i.e., those to the left of the plot) are far more likely to be relegated whereas it’s very hard to win the league, or qualify for the champions league, without controlling a majority of the ball. The only real outlier is ... Everton’s qualification in ’04-05.
It’s all well and good to know that hogging shots leads to points, but is it a repeatable skill or based more on luck? In 2013, Grayson answered the question with this graph:
His conclusion:
In summary – total shots are an excellent indicator of how good a team is. The fact that they stabilise early on in the season is really useful too. TSR undoubtedly has its flaws, but it is truly amazing to me that something so simple does so damn well at predicting the Premiership knowing only a team's TSR from last season with no adjustment for score effects, personnel changes, or shot quality.
Since then, expected-goals data has added more nuance and context to something like TSR, as it accounts for shot positioning, shot type, the pass that led to the shot, and now even defensive pressure and positioning, too. But still, at the core of the sport still sits the concept of the shot or the chance. It’s quite simple, right? The more shots you allow, the more chances your opponent has to score and vice versa. Wayne Gretzky and all that. Adjusting for chance quality creates outliers and allows for more granular comparisons, but broadly speaking, the best soccer teams in the world are the ones who limit the chances they allow and increase the number they create. It’s a simple probability game, but the shot count is a proxy for how well a team has mastered the various aspects of game control, too.
And so: Arsenal. Laudatory profiles have been written about the transformation Mikel Arteta has forced the club to undergo in his first stint as a head coach. On the back of recent results, Arteta has been promoted from head coach to manager, where he’ll now have more of a say in transfers, the youth team, and as the commentators on NBC Sports this weekend noted, he’s even involved in the science department! Yet, despite the consistently positive press and his growing influence over things beyond the things he was hired to control, his team still hasn’t been able to get control over the ever-important shots.
Over the weekend, Arsenal were outshot, at home, by West Ham United, 14 to 7. This was Arteta’s 22nd Premier League game in charge of the club, and it marked the 16th time his team had been outshot by its opponent. Through those 22 matches, Arteta’s Arsenal have taken 42.8 percent of the shots. (All data via Stats Perform.) You can slide your finger across the x-axis on Grayson’s first graph above to get a sense of what kind of points total that performance typically produces. Here’s how Arsenal compare to all the other Big Five clubs since Arteta was hired. (Ignore the huge outliers on the edges; they’re newly relegated clubs.) Per Stats Perform:
The best teams in the world are all in the upper-right. Meanwhile, the teams in the upper-left quadrant are the ones whose point totals are exceeding their shot shares by a historically unsustainable amount. Among the 108 clubs to play in the Big Five since Arteta took over, Arsenal rank 83rd in TSR but 25th in points per game.
Focusing only on the Premier League, Arsenal sit 16th in TSR since Arteta’s hiring, ahead of Sheffield United, Newcastle, Burnley, two teams that were relegated (Norwich and Bournemouth), and two teams that were promoted and have only played two matches (Leeds and West Brom). Stats Perform data goes back to the 2008-09 Premier League season, and the record number of points for a team with a TSR of 42.8 percent or below is 56 -- also known as Arsenal’s 2019-20 season. After that, Burnley hit 54 points twice -- last season and 2017-18 -- and Birmingham reached 50 in 2009-10. No other team in this cohort has reached the half-century point-mark. Expand the TSR up to 45 points to be a little more generous, and the record is Aston Villa’s 64 points in 09-10, but that tweak still only adds a Swansea, a West Ham, and a couple Stoke City campaigns to the 50-point cohort. Arsenal want to get back into the Champions League and eventually win the Premier League; the company they’re keeping here is closer to eventual relegation fodder.
This isn’t to say that Arteta hasn’t had an effect on the way the team plays. The only teams that average more possession are the four teams that are competing in the Champions League for England this season. Same goes for the average number of passes and number of seconds they keep the ball per uninterrupted possession. They’re also taking the highest quality shots -- xG per shot -- of any team, but that’s mainly canceled out by the fact that they’re only averaging 9.6 attempts per game, more than just Sheffield, Bournemouth, and this year’s three promoted teams. (Their overall xG differential is 13th in the Premier League under Arteta.)
Twenty-two games in, and Arteta has built a team that’s able to capably control extended possession and create a limited number of good chances from it, but despite having so much of the ball, they’ve been unable to create the raw total of chances necessary for a team of Arsenal’s ambitions. And despite their opponents not having much of the ball, they’ve been able to do what Arsenal have not, as the Gunners are conceding 12.9 shots per game under their new manager.
How to fix it? That’s a question for the guy who's leading the supposed revolution. Perhaps personnel changes will make a difference here and there, even though Grayson’s research suggests otherwise. There’s no true creator in the squad, and if you were building a team from scratch, the skillsets of Aubameyang, Lacazette, and Willian are not the ones you would choose to pair together across your front three. Except, Arsenal basically did just that, adding the 32-year-old Willian and re-signing the 31-year-old Aubameyang to long-term deals this past summer.
There also seems like a pretty clear connection in the uneven number of shots at both ends of the field and Arsenal’s inability to press. In the Arteta Era, the average uninterrupted possession in the Premier League has begun 46.7 meters from a team’s own goal. Liverpool’s average possession begins 52 meters away, and Manchester City’s starts 51 meters from their own net; no other team is north of 50. Arsenal, meanwhile, are way below average in terms of where they win the ball: 44.7 meters, ahead of only Wolves, Newcastle, Norwich, and two promoted sides (Leeds and West Brom). Better pressing, in theory, would create more opportunities on the attacking end and limit that limited amount of opposing possession from being turned into a disproportionate number of shots. To me, the defining question for the future of Arsenal is whether or not a shot-heavy, high-pressing approach can be eased into over time or whether it has to be instituted (with all the attendant growing pains) on Day One.
The trophies and the undefeated start to 20-21 are nice, but unless Arteta’s team starts to control the shot count, his version of his former club might have already peaked.