# Goalkeeper Analytics · Football Level 8: Expert

Football · Level 8: Expert · Insporta Book (https://book.insporta.app/football/level-8/goalkeeper-analytics/)

Goalkeeper Analytics in Football (Level 8: Expert) on Insporta: 100 sourced facts behind 10 tests. Covers: save percentage and its limits; and more.

How goalkeepers are measured: save percentage, post-shot xG and goals prevented, crosses, sweeping, distribution, penalties, clean sheets, records, saves by shot type and scouting keepers with data.

## Test 1: Save percentage and its limits

- Only shots on target can be saved, so they are the denominator. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- League averages usually sit around seven saves for every ten shots on target. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- A tame shot at his chest and a volley into the corner each count as one shot on target. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- When the defence stops the easy shots, the ones that get through are often clear chances. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- A blocked shot never tested the keeper, so it is not part of his record. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- With perhaps a hundred or so shots on target a season, a handful of saves moves the percentage a lot. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- Weighting each shot by its difficulty separates a keeper who faces easy shots from one who faces hard ones. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- The nearer the shot to the corners and the closer the range, the fewer are saved. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- The figure only uses shots that reached the target and could be saved. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- 75% against 68% means little if A faced easy shots and B faced hard ones; shot difficulty has to be taken into account. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))

## Test 2: Post-shot xG and goals prevented

- PSxG is measured after the strike, using where the ball was heading on goal, which is what the keeper faces. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- If the shots he faced were worth more than the goals he let in, he prevented goals. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- 40 expected minus 32 conceded leaves eight goals he kept out beyond what the shots were worth. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- A keeper's job starts with the shots heading for his goal, so those are the ones his performance is judged on. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- Conceding more goals than the PSxG of the shots faced points to below-par shot-stopping. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- A keeper behind a weak defence faces many more shots, so a rate puts him level with a busier or quieter rival. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- A few freak saves or deflections move the total, so analysts prefer several seasons. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- The total PSxG is what an average keeper would have conceded; the difference is his contribution. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- Placement away from the keeper and a short distance both raise the chance a shot on target goes in. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- A shot placed high in the corner is the hardest to reach, so its post-shot value is the highest. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))

## Test 3: Crosses stopped

- It divides the crosses he caught or punched by all the crosses into his penalty area. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- When the middle is packed, attackers go wide and deliver into the box, which the keeper must deal with. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- Tall, well-organised defenders take many crosses before the keeper needs to act. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- A punch often lands near attackers for a second ball; a catch stops the danger and starts his team's play. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- Standing slightly off his line gives him the distance to attack crosses into the six-yard box in time. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- A cross to the penalty spot is a defender's ball; one into the six-yard box is the goalkeeper's. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- Reading the flight, choosing when to come and holding on under pressure matter as much as reach. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- Setting his position early and calling loudly let him attack the ball before anyone else. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- Keepers dominate the six-yard box, sometimes reach the spot and rarely go as far as the edge. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- Claiming a cross into his box counts towards his crosses stopped, not as a save, since no shot was taken. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))

## Test 4: Sweeper actions

- It counts the times he comes out beyond his area to deal with the ball, the core of sweeping. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- A higher figure means he meets the ball further from his goal, a sign of an aggressive sweeper. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- With the defence near halfway, balls over the top land in the gap between the line and the goal. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- Coming out is only safe if he reaches the ball first; if not, the striker faces an open net. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- Outside the penalty area a goalkeeper has no more right to handle than an outfield player. (Source: IFAB Laws of the Game, Law 12)
- A keeper behind a deep line has little to sweep; the same numbers behind a high line mean much more. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- Every metre forward shortens the run to a through ball, though it leaves more of the goal to recover. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- The early read decides everything; the sprint and clearance follow from it. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- The higher the defensive line, the larger the area between it and the goal that the keeper protects. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- Clearing the ball beyond his penalty area is exactly the sweeper action counted in #OPA. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))

## Test 5: Distribution numbers

- Launched passes are the long ones; the percentage shows how often he goes long. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- Keepers are now expected to pass to centre-backs and midfielders rather than kick long by default. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- Short averages come from teams that play out; long averages from teams that go direct. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- Simple passes to an unmarked centre-back almost always arrive, but they do not move the team forward. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- The coach often decides whether goal kicks go short or long, so they say more about the plan than the keeper. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- Opponents press the keeper to force errors, so his calm under pressure matters for a team that plays out. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- Catching a cross and throwing at once can release a runner before the opponent recovers. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- The pass inside the box covers a few metres, a throw to the flank more, and a long goal kick most. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- The speed of the release decides whether the opponent has time to get back. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- B sends 62% of his passes over 40 yards, against 15% for A, which is the mark of a team that goes long. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))

## Test 6: Penalties and the goalkeeper

- Around 75-80% of penalties go in; the rest are saved or miss the target. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- A keeper may face five or six penalties a season, far too few to tell skill from luck. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- Krul saved from Bryan Ruiz and Michael Umaña, and the Netherlands beat Costa Rica 4-3 on penalties. (Source: Competition records (Premier League, Serie A, FIFA))
- Martínez saved from Kingsley Coman, Aurélien Tchouaméni missed, and Argentina won the shoot-out 4-2. (Source: Competition records (Premier League, Serie A, FIFA))
- Records of where takers usually shoot, and how they approach the ball, give the keeper tendencies to work with. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- One penalty is worth about three-quarters of a goal, so a couple of them can outweigh a whole run of open-play saves. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- Van Gaal's Krul change in 2014 is the best-known example: the fresh keeper's presence was part of the plan. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- The change was made in the 120th minute, and Krul's two saves decided the tie. (Source: Competition records (Premier League, Serie A, FIFA))
- Most penalties are scored; saves are the next most common outcome, and kicks off the post or bar are rarer. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- Cillessen started the match; Krul came on for the shoot-out against Costa Rica and saved two kicks. (Source: Competition records (Premier League, Serie A, FIFA))

## Test 7: Clean sheets as a statistic

- A clean sheet is a match with no goals against, credited to the goalkeeper who played it. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- The Golden Glove, awarded since 2004-05, rewards the season's clean-sheet leader. (Source: Competition records (Premier League, Serie A, FIFA))
- A strong defence that allows few shots can give an average keeper many clean sheets. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- Čech kept most of them for Chelsea and added more with Arsenal before retiring in 2019. (Source: Competition records (Premier League, Serie A, FIFA))
- Čech's 24 clean sheets came in Chelsea's 38-match title season under José Mourinho. (Source: Competition records (Premier League, Serie A, FIFA))
- Behind a weak defence he may make many hard saves, which a clean-sheet count never rewards. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- Comparing goals conceded with the quality of shots faced separates the keeper's work from the defence's. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- Clean sheets follow team strength: the better the side, the fewer chances its keeper faces. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- The clean-sheet count is a starting point; shot quality and time show what the keeper himself contributed. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- Twice as many clean sheets says a lot about the team; shot quality and goals prevented say more about the keeper. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))

## Test 8: Goalkeeping records

- Yashin, of Dynamo Moscow and the Soviet Union, won it in 1963. (Source: Competition records (Premier League, Serie A, FIFA))
- The Yashin Trophy was first presented in 2019 to Liverpool's Alisson. (Source: Competition records (Premier League, Serie A, FIFA))
- Kahn won the Golden Ball in 2002 even though Germany lost the final 2-0 to Brazil. (Source: Competition records (Premier League, Serie A, FIFA))
- Buffon's run for Juventus beat Sebastiano Rossi's 929 minutes for Milan from 1994. (Source: Competition records (Premier League, Serie A, FIFA))
- Zoff's run lasted from 1972 until Haiti scored against Italy at the 1974 World Cup. (Source: Competition records (Premier League, Serie A, FIFA))
- Zenga went 517 minutes without conceding until Claudio Caniggia's header in the semi-final. (Source: Competition records (Premier League, Serie A, FIFA))
- Buffon passed Paolo Maldini's total in 2020 and finished with 657 Serie A matches. (Source: Competition records (Premier League, Serie A, FIFA))
- Yashin's award came in 1963, Kahn's in 2002 and Alisson's in 2019. (Source: Competition records (Premier League, Serie A, FIFA))
- Zenga managed 517 minutes, Rossi 929 and Zoff 1,142. (Source: Competition records (Premier League, Serie A, FIFA))
- Buffon's 974 minutes for Juventus in 2016 broke Rossi's Serie A record of 929. (Source: Competition records (Premier League, Serie A, FIFA))

## Test 9: Saves by shot type

- Reflexes at close range, handling from distance and one-on-ones call on different abilities. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- Shots from outside the box travel far and are often central, so keepers save most of them. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- With no defender to help, the shooter has time and angle, and the keeper can only narrow it. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- A keeper sets himself for the original line, and a late touch leaves him wrong-footed. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- Headers are usually from close in and change direction quickly, so they test reflexes more than positioning. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- Splitting by type can reveal a strength, such as coming out quickly, that the overall figure hides. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- Whether he was set, how far off his line and how he moved show why the save was or was not made. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- The closer and more unopposed the shooter, the lower the save rate. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- Closing the angle and being set at the moment of the shot give him the best chance. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- At 38% his one-on-one save rate is far below his rates against long shots and headers. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))

## Test 10: Scouting goalkeepers with data

- Shot-stopping numbers swing from year to year, so a pattern over seasons is far more reliable. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- A modern keeper is judged on saving, claiming, covering space and passing, and each has its own data. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- A keeper in a possession side sweeps and passes more; one behind a low block faces more crosses and shots. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- Numbers earned against weaker attacks may fall when he faces sharper finishing week after week. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- How he organises his defence and deals with pressure in the box is easiest to judge in the stadium. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- A keeper who passes well under pressure lets the team start attacks cleanly instead of kicking long. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- A single mistake near goal usually ends in a goal, so even a few a season carry a high cost. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- Shot-stopping narrows the list first; the other skills, video and a visit build the full picture of the keeper. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- The more shots faced, the more luck cancels out and the clearer his real level becomes. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))
- Two strongly positive seasons and one slightly negative one point to a good shot-stopper with normal variation. (Source: Goalkeeping analytics (FBref/Opta, StatsBomb definitions))

Sources: IFAB Laws of the Game / FIFA & UEFA technical reports / Opta, StatsBomb and FBref definitions / club and analyst publications / peer-reviewed research

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