Expected Goals Against (xGA)
Expected goals against sums the values of the attempts a defence conceded, which describes the quality of the chances the opponent created rather than the number of goals that followed.
What it means
It is the defensive counterpart of expected goals, and its difference from goals conceded measures how much of a defensive record was the goalkeeper and how much was luck.
Why it matters
It separates a defence that concedes few good chances from one that concedes many and is rescued by its keeper, which goal-based defensive records cannot do.
Where it is used
Defensive profiling, goalkeeper assessment and the analysis of a side's underlying level against its results.
Where it misleads
It measures the chances conceded, not the defending, so it says nothing about how hard the defence worked. It is biased by game state, since a losing side concedes fewer chances because the opponent stops attacking.
Key points
- It describes chance quality conceded, not defensive quality.
- Compare it with goals conceded to isolate the keeper's contribution.
- Game state biases it, as it biases every match-level figure.
- Split open-play and set-piece concessions before comparing sides.
- Sample size applies: a season is the minimum useful window.
- Report it with the shot count conceded.
Nothing here is a forecast; the number describes play that has already happened and the limits above describe what it cannot reach.