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Raheem Sterling Proves That Everything You Know About Goal-Scoring Is Wrong

With 14 goals in 22 games, the Manchester City attacker is the poster boy for one of the key findings of the nascent field of soccer analytics: It doesn’t matter how you shoot, as long as you’re shooting

Getty Images/Ringer illustration

Raheem Sterling has scored 14 goals in the Premier League this season for Manchester City, putting him right in the thick of the competition’s Golden Boot race, along with the likes of Tottenham’s Harry Kane, Liverpool’s Mohamed Salah, and his teammate, Sergio Aguero.

Of the 23-year-old Englishman’s haul, 13 have come inside the box, five of which were inside the 6-yard area. Five goals have come after the 80th minute of a match, helping Pep Guardiola’s side secure vital points on their journey to utter domination in his second season in England.

And yet, there is a conundrum about Sterling’s reputation as a goal scorer: A popular opinion persists that he’s, well, just bad at shooting.

Fans and pundits alike have criticized the winger’s shooting technique. In 2015, Paul Scholes, a Manchester United legend renowned for his technique with the ball, wrote in a column for The Independent, “There is an observation I find myself coming back to every time I watch Sterling. I don’t rate him that highly as a striker of the ball and by that I mean, literally, how he kicks it.”

Two years later, as the £50 million signing revels in the increasing silence of his doubters, his stats raise a question: How can one of the top scorers in the best professional football league in the world be bad at shooting?

To answer that question, let’s start with another one: How important is finishing to scoring?

The field of football analytics still trails behind its peers in other major sports, but there have already been a few discoveries that might change the way we think about the game. The strongest finding is that getting chances is more important than finishing them.

“People have always believed that finishing is a genuine skill but, except in truly exceptional cases like Leo Messi or Luis Suárez, we’re only now close to proving its existence conclusively with data, at least as far as publicly available research is concerned,” said Marek Kwiatkowski, a football analytics consultant.

Expected-goals stats (xG) have become so popular that they’re featured on the BBC’s Premier League highlights show, Match of the Day, as well as referred to publicly by Arsenal boss Arsène Wenger. These models attempt to predict the probability of a goal from a shot, taking into account its location, whether it is a header, and a host of other potential factors. With careful methodology, we can include the identity of the player when calculating the expected number — i.e. a Messi shot should be worth more than a shot from the same exact location by another player — but that still adds a only tiny bit more context.

“This difficulty [in evaluating finishing skill],” Kwiatkowski said, “is due to the fact that the player effect is small compared to that of the player-independent circumstances of the shot, like location or type of assist.”

In effect, a shot’s location tells us a lot about the likelihood of a goal, whereas the identity of the player — and their implied finishing ability — tells us relatively little.

Stratabet is a soccer betting company that produces more in-depth proprietary data on shots than other providers. Its team of analysts mark the “shot quality” of a particular strike on a scale of zero to five from the point of view of the shooter. This is based on how well the shot was struck (i.e. the “technique”) and where it is headed on the goalmouth relative to the goalkeeper’s positioning.

In the video below, the striker gets into an absurdly fortuitous situation, with an open goal and the ball by the penalty spot. Before he takes the shot, most models would, conservatively, assign a 90 percent probability of a goal. After his dreadful attempt, though, hypothetically assigned a zero for shot quality, it would earn a zero percent probability.

While that’s an extreme, one-in-50-lifetimes example, including shot quality in an otherwise typical xG model shows that finishing skill does have an effect on the number of goals scored in a given season, but only at the margins.

xG added from shot quality

Of the top goal scorers in Europe last season, Messi was predictably the best finisher, adding 32 percent to the xG of his chances with the quality of shots. Kane is next, added 26 percent to his xG total based on chance quality alone. Roma’s Edin Dzeko lost 7 percent through the quality of his strikes, while PSG’s Edinson Cavani and Inter Milan’s Mauro Icardi lost 8 and 12 percent, respectively. Of all players to have scored more than five open-play goals in Europe’s biggest five competitions last year, the average xG added from their shot quality is just 8 percent.

Here’s who added the most xG to their chances last season:

Top finishers, players to add > 3 xG from shot quality

And here’s who detracted the most:

Worst finishers, players to lose > 2.5 xG from shot quality

For some of the players with fewer chances overall, the quality of their shots may have defined their seasons. Federico Bernardeschi was signed from Fiorentina by Juventus for €40 million in the summer, as he scored seven open-play goals rather than the three implied by a chance quality model because of his finishing. But for players like Cavani, who lost three xG from the quality of his shots but nonetheless scored 27 open-play goals, the chances themselves are far more important.

Finishing matters, but the ability to bend a ball into the upper corner pales in comparison with the ability to get in position to take the shot.

Although the relative importance of chance-getting may be counterintuitive to fans, it is nothing new to those developing the next generation of superstars. Jeremy Steele is a qualified UEFA A coach who has worked in academy and first-team roles at the likes of Chelsea, Barnet, Brentford, West Ham United, and Stoke City. He is now the managing director of Analytics FC, a consultancy that provides software and advice to clubs looking to capitalize on the insights available from an analytical approach to the game.

“To say finishing skill doesn’t exist is ludicrous,” Steele said. “Obviously, some players fare better than others when faced with a good chance, while others have finishing techniques which are less likely to break down under pressure from defenders.

“However, there are traits that are slightly more important determinants to scoring,” he said. “Movement, timing, body position, and first touch. It’s not a coincidence that Thomas Muller, Jermain Defoe, or Javier Hernández continue to find themselves in dangerous positions in the box so often, or that their first touch sets them up for a shot so quickly. It’s no accident that Cristiano Ronaldo ghosts in at the far post for headers so often, or indeed that Olivier Giroud gets across the near post so often for Arsenal.”

Bayern Munich’s Muller typifies the importance of the subtle facets of chance getting. Known in German as a raumdeuter (which translates to “space investigator”), his intelligent movement often makes up for the fact that he is not as technically gifted as some of the other players on the list.

“Of course, repetition of finishing from different angles, different passes, and on different surfaces is important,” Steele says when asked about priorities in a striker’s development. “Most of the coaching detail, though, is normally around where to run, the timing of these runs, how to receive the ball, and how to turn or roll an opponent to get a shot off. There’s far more to center-forward play than simply the act of striking the ball.”

Raheem Sterling himself has made reference to his desire to score more goals. In March, he lamented during a Guardian interview that he “should have so many more goals. It’s terrible.” Halfway through the 2017–18 Premier League season, he has already doubled his previous highest goals tally for a campaign, and he has done so primarily by getting himself a higher number of quality chances. Per the shot quality xG model, Sterling had roughly 6 xG last season. This time around, he already has nearly 11 — and despite his reputation, his finishing has helped a tiny bit.

xG added from shot quality, top open-play goal scorers

Álvaro Morata, widely derided for his finishing against Arsenal in Chelsea’s first match of 2018, is the only player to score more than six open-play goals in the Premier League while also detracting from the quality of their chances with their shooting. Mohamed Salah, meanwhile, who has been similarly accused of missing chances, has added 3.7 xG from his shot quality this season. Both cases illuminate the streakiness of finishing for most players. While they scored an identical 15 open-play goals last season, Salah lost 18 percent of the xG of his chances at Roma through his shot quality, while Morata added 23 percent.

The development in Sterling’s chance-getting ability, while more difficult to see with the naked eye than finishing skill is, is exemplified by a viral clip that shows him working with Guardiola on movement that led directly to a goal.

Indeed, the Catalan manager has remarked in press conferences that the English winger has been working hard on his improving goal-scoring prowess with assistant manager Mikel Arteta. Naturally, we might assume that, given it is Sterling’s most glaring weakness, his extra sessions were made up primarily of shooting practice. But, according to Guardiola, they are focusing “specifically on the last action on the pitch — that control in the last moment to make the right movement in the final three or four metres.”

How can one of the top scorers in the Premier League this season be bad at shooting? The answer, in the end, is deceptively simple: Shooting ability matters less than we tend to think it does. As Raheem Sterling has illustrated, being a top goal scorer is less about taking the chances, and much more about getting them in the first place.

Bobby Gardiner is a product manager at Football Whispers. He writes about football through an analytical lens, with a particular interest in team tactics.

This article was written with the aid of StrataData, which powers the StrataBet Sports Trading platform.