What Is Goals Prevented in Football?
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| Goals Prevented measures goalkeeper shot-stopping performance by comparing xGOT with goals conceded. A football goalkeeper making a save with an analytics graphic explaining Goals Prevented, xGOT, expected goals on target and goals conceded. |
Goals Prevented is a modern football statistic used primarily to measure how effectively a goalkeeper stops shots compared with what would be expected from an average goalkeeper.
Unlike a simple save count, Goals Prevented considers the quality and difficulty of the shots a goalkeeper faces. A goalkeeper who makes five saves from relatively easy efforts has not necessarily had the same shot-stopping performance as a goalkeeper who makes five saves from difficult shots.
The statistic is commonly calculated using expected goals on target (xGOT), also known as post-shot expected goals (PSxG).
A simplified formula is:
Goals Prevented = xGOT Faced − Goals Conceded
A positive number generally means the goalkeeper conceded fewer goals than the post-shot model expected. A negative number means the goalkeeper conceded more than expected.
This makes Goals Prevented particularly useful when analysing goalkeeper shot-stopping performance.
What Does Goals Prevented Mean?
Goals Prevented estimates how many goals a goalkeeper has stopped above or below expectation based on the shots on target they faced.
For example, imagine a goalkeeper faces several shots during a match with a combined xGOT of 2.4.
If the goalkeeper concedes only 1 goal, the calculation would be:
2.4 − 1 = +1.4 Goals Prevented
In simplified terms, the goalkeeper prevented approximately 1.4 goals more than expected from those shots.
On the other hand, if the goalkeeper conceded three goals:
2.4 − 3 = −0.6 Goals Prevented
That indicates the goalkeeper conceded more goals than the model expected from the shots faced.
Opta describes the metric as a way of comparing the quality of shots on target with the goals actually conceded, helping evaluate goalkeeper shot-stopping separately from the defensive work in front of the goalkeeper.
How Is Goals Prevented Calculated?
The calculation is relatively straightforward once you understand xGOT.
Formula
Goals Prevented = xGOT Faced − Goals Conceded
There are two important numbers:
- xGOT faced
- Goals conceded
Let's examine both.
1. xGOT Faced
xGOT stands for Expected Goals on Target.
It is related to xG, but it evaluates the shot after it has been struck. The model considers factors such as where the ball is heading within the goal and the characteristics of the attempt.
For example, two shots could come from almost exactly the same location.
One could be hit directly at the goalkeeper.
The other could be placed toward the corner.
Although the opportunities may have similar pre-shot xG, the second shot can have a higher post-shot value because it is more difficult for the goalkeeper to stop.
Explore how expected goals (xG) are used in football.
2. Goals Conceded
The second part is simply the number of goals the goalkeeper actually concedes from the relevant shots.
Suppose a goalkeeper faces shots with a combined xGOT of 4.8 and concedes 3 goals.
The calculation becomes:
4.8 − 3 = +1.8 Goals Prevented
The goalkeeper therefore has a Goals Prevented figure of +1.8.
Positive vs Negative Goals Prevented
Understanding the sign of the number is important.
| Goals Prevented | Basic interpretation |
|---|---|
| +2.0 | Conceded around two fewer goals than expected |
| +1.0 | Conceded around one fewer goal than expected |
| 0.0 | Conceded roughly what the model expected |
| -1.0 | Conceded around one more goal than expected |
| -2.0 | Conceded around two more goals than expected |
A positive Goals Prevented figure indicates that the goalkeeper has saved more goals than expected based on the post-shot quality of the shots faced.
A negative figure indicates that more goals were conceded than the model expected.
However, the number should not be interpreted in isolation.
Example of Goals Prevented
Imagine a goalkeeper faces five shots on target.
Their individual xGOT values are:
- Shot 1: 0.20
- Shot 2: 0.70
- Shot 3: 0.35
- Shot 4: 0.45
- Shot 5: 0.30
The combined xGOT is:
0.20 + 0.70 + 0.35 + 0.45 + 0.30 = 2.00
The goalkeeper therefore faced 2.00 xGOT.
Suppose the goalkeeper concedes only one goal.
Goals Prevented = 2.00 − 1.00
Goals Prevented = +1.00
In this example, the goalkeeper prevented approximately one goal compared with the expectation generated by the post-shot model.
Why Goals Prevented Is Different From Saves
A basic save statistic tells you how many shots a goalkeeper stopped.
But it doesn't tell you how difficult those shots were.
Consider two goalkeepers:
| Goalkeeper | Saves | xGOT Faced | Goals Conceded | Goals Prevented |
|---|---|---|---|---|
| Goalkeeper A | 5 | 1.5 | 1 | +0.5 |
| Goalkeeper B | 5 | 3.0 | 1 | +2.0 |
Both goalkeepers made five saves and conceded one goal.
But Goalkeeper B faced shots with a much higher combined post-shot expected value.
That is why Goals Prevented can provide additional context that a raw save count cannot.
For better understanding, Check our guide: How to Read Football Match Statistics.
Goals Prevented vs xG
Goals Prevented and xG are related, but they answer different questions.
xG asks:
How likely was a chance to result in a goal before the shot was taken?
Goals Prevented asks:
How many goals did the goalkeeper prevent compared with what the shots on target were expected to produce?
For example, a team may have an xG of 2.5 but score only one goal.
That tells you something about the team's finishing.
If the opponent's goalkeeper has a positive Goals Prevented figure, however, some of the difference may be explained by the goalkeeper making saves from difficult shots.
This is one reason analysts distinguish between chance creation, finishing and goalkeeping.
Goals Prevented vs xGOT
This is an especially important distinction.
xGOT measures the expected scoring probability of shots on target after considering where the shot was directed.
Goals Prevented uses that information to evaluate the goalkeeper.
A simplified relationship is:
xGOT Faced → Expected goals conceded → Actual goals conceded → Goals Prevented
For example:
10.5 xGOT faced − 8 goals conceded = +2.5 Goals Prevented
The goalkeeper therefore conceded 2.5 fewer goals than the post-shot model expected.
Opta's explanation of xGOT shows why this is useful: xGOT accounts for the quality of shots on target and can therefore be used to estimate how many goals an average goalkeeper would be expected to concede from those attempts.
For a better explanation, see What Is xGOT?
Does a High Goals Prevented Number Always Mean a Goalkeeper Is Better?
Not necessarily.
Goals Prevented is useful, but it should be interpreted alongside other goalkeeper statistics.
One important issue is sample size.
A goalkeeper who plays two matches and records +2.5 Goals Prevented has not necessarily demonstrated the same level of performance over an entire season as a goalkeeper who records +2.5 across 30 matches.
Another consideration is the statistical model itself.
Different providers can use different methodologies, datasets and models to calculate post-shot expected goals. Therefore, Goals Prevented numbers from different providers should not automatically be treated as identical.
Opta, for example, uses its own xGOT methodology, while other data providers can produce different post-shot models.
Why Goals Prevented Is Useful
Goals Prevented can help analysts answer questions that traditional goalkeeper statistics cannot fully answer.
1. Measuring shot-stopping
It provides a way of evaluating whether a goalkeeper is conceding more or fewer goals than expected from the shots faced.
2. Adding context to save numbers
Five saves from difficult shots are different from five saves from relatively easy attempts.
3. Comparing goalkeeper performances
Over sufficiently large samples, the statistic can help compare shot-stopping performance between goalkeepers.
4. Analysing individual matches
A goalkeeper can have a low save count but still record a strong Goals Prevented figure if the shots faced were difficult.
5. Supporting scouting analysis
Analysts can combine Goals Prevented with other goalkeeper statistics to build a more complete picture of performance.
What Goals Prevented Does Not Tell You
Goals Prevented primarily concerns shot-stopping.
It does not provide a complete evaluation of a goalkeeper.
For example, it does not by itself tell you how well a goalkeeper:
- Claims crosses
- Commands the penalty area
- Sweeps behind the defensive line
- Plays with their feet
- Distributes the ball
- Organises the defence
- Deals with crosses
- Makes decisions when leaving the goal
Therefore, a goalkeeper's overall performance should be assessed using multiple statistics and video analysis.
Can Goals Prevented Be Negative?
Yes.
A goalkeeper can have a negative Goals Prevented value.
Suppose the shots faced have a combined xGOT of 3.2, but the goalkeeper concedes 4 goals.
The calculation is:
3.2 − 4 = −0.8
The goalkeeper's Goals Prevented figure is therefore −0.8.
This means the goalkeeper conceded more goals than the post-shot model expected from the shots faced.
A negative number does not automatically explain why the goals were conceded. It simply describes the goalkeeper's result relative to the model's expectation.
Goals Prevented and Clean Sheets
Goals Prevented should not be confused with clean sheets.
A clean sheet simply means a goalkeeper did not concede a goal.
A goalkeeper can keep a clean sheet without recording a large positive Goals Prevented figure if the opponent produces relatively easy shots.
Conversely, a goalkeeper can concede two goals while recording a strong Goals Prevented figure if they make several difficult saves.
For example, a goalkeeper could face 3.5 xGOT, concede two goals and record:
3.5 − 2.0 = +1.5 Goals Prevented
The goalkeeper conceded twice but still prevented approximately 1.5 goals relative to the model.
Goals Prevented and Defensive Quality
One of the biggest advantages of the statistic is that it attempts to separate goalkeeper shot-stopping from the defensive work happening in front of the goalkeeper.
A strong defence can limit opponents to low-quality shots.
A goalkeeper behind that defence might face very few difficult attempts.
Another goalkeeper could face numerous high-quality shots because their defence allows opponents to create dangerous opportunities.
Goals Prevented considers the shots that actually reach the target, rather than simply counting how many shots a goalkeeper faced. Opta has used the metric specifically to account for shot quality when assessing goalkeeper performance.
That makes it different from simply looking at saves or shots faced.
How to Read Goals Prevented on a Football Statistics Website
When you see a goalkeeper's Goals Prevented number, look at several things together:
1. Goals Prevented
Did the goalkeeper concede fewer or more goals than expected?
2. xGOT faced
How difficult were the shots on target?
3. Goals conceded
How many goals actually went in?
4. Shots on target faced
How many attempts did the goalkeeper have to deal with?
5. Minutes played
Has the goalkeeper accumulated enough playing time for the comparison to be meaningful?
6. Competition and season
Make sure you're comparing players within a similar context.
This prevents a single statistic from being taken out of context.
A Simple Way to Remember Goals Prevented
The easiest way to remember the statistic is:
Goals Prevented compares expected goals from shots on target with the goals the goalkeeper actually conceded.
Think of it as:
Expected goals conceded − actual goals conceded = Goals Prevented
The more goals a goalkeeper saves relative to the model's expectation, the more positive the number becomes.
Frequently Asked Questions
What is Goals Prevented in football?
Goals Prevented is a goalkeeper statistic that estimates how many goals a goalkeeper prevented compared with the expected goals from the shots on target they faced.
How is Goals Prevented calculated?
A common simplified formula is:
Goals Prevented = xGOT faced − goals conceded.
The xGOT figure represents the post-shot expected scoring value of the goalkeeper's shots on target faced.
Is a positive Goals Prevented good?
A positive figure means the goalkeeper conceded fewer goals than the post-shot model expected from the shots faced. It is generally interpreted as evidence of positive shot-stopping relative to that model.
Can Goals Prevented be negative?
Yes. A negative figure means the goalkeeper conceded more goals than the model expected from the shots faced.
Is Goals Prevented the same as saves?
No. Saves count the number of on-target shots stopped, while Goals Prevented considers the expected difficulty of those shots using post-shot expected goals.
What is xGOT?
xGOT means Expected Goals on Target. It evaluates the scoring probability of a shot on target after considering where the shot was directed. It is also commonly referred to as post-shot xG or PSxG, although terminology can vary between providers.
Does Goals Prevented measure the entire performance of a goalkeeper?
No. It primarily evaluates shot-stopping. Distribution, crosses, sweeping, positioning, decision-making and other goalkeeper actions require additional statistics and video analysis.
Final Takeaway
Goals Prevented is one of the more useful advanced statistics for understanding goalkeeper shot-stopping.
Instead of simply asking how many saves a goalkeeper made, it asks a more detailed question:
How many goals did the goalkeeper concede compared with the quality of the shots they faced?
The basic calculation is:
Goals Prevented = xGOT Faced − Goals Conceded
A positive value means the goalkeeper conceded fewer goals than expected, while a negative value means they conceded more than expected.
However, Goals Prevented should be used alongside xGOT, saves, save percentage, shots on target faced and playing time, rather than treated as a complete goalkeeper rating.
Article Source Credit: Sky Sports
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