I've been analysing the goalkeeper data available through FBRef as I think goalkeeping is the easiest of all positions to analyse statistically.
I've taken some of the provided ones and come up with a few transformations to create a list of metrics to score goalkeepers from the top five leagues on their league performances over this season and the previous two to create reasonable size samples.
Metric | Definition | Limitations |
Stopped Crosses % | Crosses Stopped divided by Crosses Faced | Doesn't take into account how "stoppable" a cross is, or failed cross claims |
Distance Swept /90 | Number of sweeping actions multiplied by average sweeping distance, divided by 90s played | doesn’t take into account failed sweeps which usually result in high scores quality chances |
Shot Stopping | Post-shot xG faced minus goals against, divided by post-shot xG faced | FBRef post-shot xG model doesn't take into account shot location or power |
Bad Touches /90 | Miscontrols plus dispossessions per 90 played | |
Bad Touch Ratio | Miscontrols plus dispossessions divided by total touches | |
Outside Area Touches | Touches Outside penalty area divided by total touches | |
Outside Area Touches /90 | Touches Outside penalty area per 90 played | |
Short and Medium Passes /90 | | Somewhat team style dependent |
Short and Medium Share | A ratio of short and medium passes relative to total passes | Somewhat team style dependent |
Short Accuracy | Completion percentage of short passes | |
Medium Accuracy | Completion percentage of medium passes | |
Long Accuracy | Completion percentage of long passes | |
Passing Tendancies | An average of the percentile rank of "Short and Medium Passes /90" and "Short and Medium Share" | |
Passing Accuracy | An average of the percentile rank of "Short Accuracy", "Medium Accuracy" and "Long Accuracy" | |
On Ball Comfort | An average of the percentile rank of "Bad Touches /90", "Bad Touch Ratio", "Outside Area Touches" and "Outside Area Touches /90" | |
Crosses | Percentile rank of "Stopped Crosses %" | |
Sweeping | Percentile rank of "Distance Swept /90" | |
Shot Stopping | Percentile rank of "Shot Stopping" | |
OVERALL SCORE UNWEIGHTED | An Average of each of the six above | |
OVERALL SCORE WEIGHTED | As above but each category is weighted by the amount specified | |
That then gives us the below table for the top 50 overall (Costa is highlighted as he doesn't play in a top five league and thus his data may or may not be comparable):
Lots of names you would expect, but also quite a few that I hadn't heard of: Casteels (contract expires 2024 and valued at 8m Euros on TransferMarkt), Samba (10m Euros) and Diouf (5m Euros) look very well balanced, with none of the six metrics being below average. Diogo Costa, Pau Lopez and to a lesser extent David Raya also look like good options for United.
David De Gea -
78th out of 90 goalkeepers that have played at least 50 games' worth of minutes:
If you're more of a traditionalist and value shot-stopping and command of area uber-alles, quadrupling the weight of those two metrics gives the following top 50
For a visual comparison of some we've been linked to and others we should be considering:
Conclusions
- David De Gea is either average or poor at everything a goalkeeper is required to do
- Upgrading on him can be done in an inexpensive manner
- Obviously scouting/eye-test and personality assessment would also be required before signing any of the above
You can download the Excel file from the link below and add your own weightings for each category in the first sheet ("Scoreboard"), I'd recommend filtering "90s" to at least 30 if not 50 to ensure the goalkeepers being looked at have reasonable sample sizes. The second ("Comparison Charts") allows you to create your own radar comparison chart for up to five of the goalkeepers included in the analysis.
Link to File