Quick, who’s the most valuable player in your favorite sport? If you’re a football fan, odds are you thought of a quarterback and not a defensive lineman; in basketball, it’s probably a high-volume shooter, not a rim protector; in baseball, it’s often a slugger, rarely a pitcher. Same in soccer, where the glory goes to players who score goals, not the ones who prevent them. The only goalkeeper ever to win the Ballon d’Or, soccer’s most prestigious award, was Dynamo Moscow’s Lev Yashin. He played his World Cup games for the Soviet Union, if that gives you an idea how long it’s been since anyone gave shot-stopping its due.
In a sport where a goal saved is roughly as good as a goal scored, it’s hard to say why the field is so heavily tilted toward shooters. Part of it could be that we haven’t had good ways to measure what keepers do. “A guy who gets a lot of clean sheets may just have a good defense,” said Brian Bilello, the president of Major League Soccer’s New England Revolution. Save percentage isn’t an ideal metric, either, since a keeper who stops a higher share of his shots on target may be facing easier shots from distance. “I would say goalkeepers are misvalued,” Bilello said.
The Revs have good reason to want to change that. Their goalkeeper, a 27-year-old named Matt Turner, is the best shot-stopper in America. Though he started playing relatively late, Turner has been head and shoulders above everyone else since reaching MLS in 2018. At this month’s Gold Cup, he could play his first competitive game for his country. Journalists have been “writing article after article about him and how good he is, the best shot-stopper in the history of the league and all that stuff,” the U.S. Men’s National Team manager Gregg Berhalter said last week. “But to a certain extent, I agree with them.”
How do we know how good Turner is? The stats case starts with expected goals. Usually xG measures a shot’s likelihood of scoring based on distance, angle, the body part with which the shot was taken and other context at the instant the shooter strikes the ball. But there’s another version called post-shot expected goals, which measures the same probability at the moment the shot crosses the goal line — or would cross it, if the keeper didn’t save it. By including information about ball placement, PSxG can give us an idea of how many goals a keeper concedes compared with how an average shot-stopper would have done against the same shots.
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In Turner’s case, the difference is huge. According to American Soccer Analysis, he’s saved over 22 more goals than expected since 2018. The second-place keeper has less than 15. Turner’s goals conceded divided by xG ratio is 0.82, or about four goals allowed for every five that an average shot-stopper would have conceded. No active MLS keeper comes close. Shot-stopping rates take a few seasons to stabilize, but after facing nearly 400 shots on target, Turner’s is the best on record.
“I think having a positive expected goals [difference] is huge for the team,” Turner said. “Your defense can’t stop every shot for you.” He credits his shot-stopping to a lot of different things, including playing dodgeball and baseball as a kid. “I think it’s athleticism, positioning and most importantly, timing,” he said. “People don’t make as many saves when they’re not set. But that’s also understanding patterns, when to be set, what it looks like when someone’s about to take a shot versus play a dribble or make a pass in behind.”
But saving shots is only part of a goalkeeper’s job, which also includes organizing the defense, passing out of the back and claiming balls in what the Revs’ goalkeeper coach, Kevin Hitchcock, calls the keeper’s “living room.” Hitchcock picked Turner as a starter based on his athleticism, but they’ve spent the last few years working on the rest of his game, trying to develop him into a crisp-passing, aggressive-defending modern keeper.
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American Soccer Analysis has a way to measure those other skills, too. The latest trend in soccer analytics is a type of model, sometimes called “expected possession value,” that estimates how much every touch changes a team’s chances of scoring and conceding. ASA’s version, dubbed “goals added,” or g+ for short, recently expanded to include goalkeepers. Every time a keeper touches the ball — whether it’s a pass, a punch, a sweeper tackle, a claimed cross or a save — g+ assigns some positive or negative goal value based on that action’s likely effect on the scoreline.
Turner’s non-shot-stopping g+ is pretty good, but the important thing here is that the differences among keepers are tiny: Compared to an average keeper, the leader over the past four seasons has added about 0.03 goals each game with all touches other than saves. Turner’s shot-stopping, which g+ accounts for by subtracting goals from post-shot expected goals, has added more than 10 times that amount. As far as ASA can measure right now, denying shots is by far the biggest difference-maker in a keeper’s skillset.
By valuing every kind of touch in fractions of a goal, g+ makes it possible to compare players across positions. In the three and a half years since he entered the league, Turner has racked up 25.6 more total goals added than an average player at his position. The three attacking players who have won the league’s MVP award in that time, Alejandro Pozuelo, Carlos Vela, and Josef Martínez, have 20.2 g+ above average — combined.
|Goals Added Over Positional Average
Like much of advanced soccer analytics, goalkeeping stats are still in their infancy. Goals added is based on event data, which can’t see what’s happening off the ball. That makes it tricky to judge a keeper’s decision-making in the build-up or whether he should have come for a cross. Future metrics might punish keepers for the danger of an unclaimed corner kick, for example, or better capture the value of building out of the back.
“I don’t really want to say, ‘Who cares how many short passes you make if you’re not advancing the ball?’” said Turner, whose average pass distance this year is second-longest among MLS keepers. “The game is evolving, and I feel like that’s an area where people want to see goalkeepers starting to take a little more risks. But I also think the short passing leads to more goals against, because you make a mistake or you pass the ball to a teammate who makes a mistake.”
If he’s going to fight his way up the U.S. depth chart during World Cup Qualifiers this fall, Turner will have to convince coaches that he’s a complete modern keeper — or that his shot-stopping is so valuable that average passing or sweeping isn’t a problem. Berhalter may be coming around to that idea. Before Turner’s first international friendly last winter, the coach pulled him aside. “He told me, ‘Listen, if you don’t feel comfortable taking a risk, don’t take the risk. You’re here for a reason,’” Turner recalled. “‘So just go out there and play your game.’”
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