Save percentages

When I looked at the Shots on Target data yesterday, I mentioned how Bournemouth were conceding more than they should be. A key point of strength – or weakness – in any defence is the goalkeeper. Could the performance of Bournemouth keeper Artur Boruc be playing a role in the Cherries only returning one clean sheet this season, despite the team having the second lowest Shots on Target conceded figures in the Premier League this year?

The National Hockey League season has just begun and in that league save percentage is a major statistic used to judge goaltender performance. I hardly see it mentioned in relation to the Premier League – at least not in the places I usually go looking for information – so I decided to create my own chart of goalkeeper save percentages.

Goalkeeper save percentages GW1-8 2015-16

The chart shows save percentages with keepers ordered by minutes played. All those from Petr Cech up have played every minute of every game. Everyone from Sergio Romero up has played in at half or more of their club’s games this season.

The data was constructed by assuming that a ball hit towards goal either ends in a save or a goal conceded. This is a rough and ready approach that may be skewed slightly by own goals, but I thought it was more manageable than comparing saves to shots on target because that too had problems and making adjustments for it would require going through each game with a fine-tooth comb. Despite the caution, I think this will serve the purpose of discovering the best and worst performers.

Southampton stopper Maarten Stekelenburg and Bournemouth’s Boruc  have the lowest save percentages of the regular starters despite their teams having the lowest and third lowest Shots on Target Conceded numbers respectively in the Premier League. Are teams only shooting against these sides when they get gilt-edged chances or have Stekelenburg and Boruc been poor? This could be fruitful area for more research when I look at defences individually.



Last year the average save percentage for Premier League keepers was 69 per cent. This year it is at 70 per cent. This holds out the tantalizing prospect that if Stekelenburg and Boruc can raise their save percentages to the league norm, their teams could be good sources for clean sheet points.

At the other end of the scale Wayne Hennessey has a 100 per cent save percentage in the two games since he took over between the posts for Crystal Palace. Clearly he won’t sustain that for the whole season, but what’s more interesting is that the man he replaced, Alex McCarthy, has the second highest save percentage among goalies who have played at least six games this season. His 81 per cent save percentage is just one percent below Cech, the league leader, and 11 per cent above the league average. That suggests Alex McCarthy was unlucky to be dropped.

Closer inspection reveals that McCarthy conceded a goal or made a save every 15 minutes, but Hennessey has only had to make a save every 45 minutes. McCarthy’s opponents included Manchester City, Arsenal, Tottenham and Chelsea, the first three of which have each registered more Shots on Target this season than Hennessey’s opposition, Watford and West Bromwich Albion, have managed combined. This suggests no one should be getting carried away with the idea that Hennessey is the magic ingredient that has suddenly turned the Eagles into a defensive powerhouse.



Finally, Leicester have failed to record a clean sheet this season. No team has conceded more Shots on Target than the Foxes have at home, but only two teams have conceded fewer Shots on Target on their travels. Kasper Schmeichel has failed to keep a clean sheet this season, but if he can pull his save percentage up from 59 per cent maybe we will start to see that change – away from the King Power Stadium at least.

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5 thoughts on “Save percentages

  1. the cromument one says:

    Ha! I love the NHL reference.
    But I do believe that in football much more so than hockey, the quality of the shots makes a difference. Many shots in football are simply not stoppable. In hockey, when a goalie gets 30 shots a game, the save percentage is much more meaningful.
    But the exercise is interesting nevertheless. But more interesting than save percentage might be goalkeeping errors that lead to a goal. Most PL keepers are capable of making terrific saves, but what separates them is their consistency.
    Go Habs Go.

    Like

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