When we started Stopper, our assumption was that tracking a goalkeeper manually is much easier than tracking an outfield player. Why? For one, their positioning is generally predictable; for another, they tend to spend less time on the ball then other players.
But is that assumption true? How many times does a goalkeeper really touch the ball in a game?
Turns out it’s surprisingly hard to find the answer. Among the best-known analysis is a study published in the Journal of Sports Science that tracked the movement patterns of 30 French League 1 matches over a period of two seasons. Among other findings, it showed that players had, on average, 47 possessions per match and 2 touches per possession. Central forwards had the fewest possessions (35) while outside defenders had the most (56) – but I couldn’t find a reference to goalkeeper possession per se.
A more recent study published in PLoSOne showed that while goalkeepers and centre forwards had the fewest touches on the ball, GKs had the longest “In Ball Control” intervals and the highest proportion of “In Ball Action” intervals with control – likely because they are allowed to catch the ball and can’t be attacked while they are holding it. Again, while informative, this study didn’t specifically track the amount of goalkeeper touches per game.
OptaStat is always a good source for detailed football data for the big leagues in soccer – doing a quick assessment of the past season, it appears that goalkeepers in the EPL average around 44 touches per game if we include the “accurate long balls” category. I suspect that is a subset of Opta’s goalkeeper passing and goal kick data, in which case the average amount of GK actions, as tracked by Opta, drop to around 37 or so per game, roughly that of a striker.
Our own Stopper data is obviously entirely focused on goalkeeper performance – and since touches per game is something that we do track (as a byproduct, not a specific data set) we thought it would be interesting to look at the numbers. With a couple hundred games of testing in the vault (both MLS and MLS Academy games, so not a clean data set), the official Stopper number for average GK touches per game clocks in at a surprisingly high 47.26 actions per game. The highest number of actions recorded in a single game was 76; the lowest on record is 32, variables that depend on style of play, opponent, defensive strength and so on.
I’m going to be keep an eye on this stat – is there a connection with wins and losses? Do keepers rated higher in Stopper also touch the ball more often? – but the bottom line is goalkeepers seem to get their hands, feet and bodies on the ball a surprising amount these days, making the #1 truly the 11th man in modern soccer!