Game state
A team 2-0 up does not play like a team 0-1 down. The score changes the chances teams take and allow, and most xG models do not know the score.
What changes with the score
Leading
Fewer shots, often better ones: counter-attacks into open space. More time spent defending deep.
Level
Both sides play their normal game; the cleanest picture of their level.
Trailing
More shots, many from distance or from crosses into a packed box: lots of low-value xG.
Why it matters for xG
- A team that scores early and sits back can "lose" the xG count and still be the better side.
- A late flurry by a losing team inflates its xG without changing the match.
- Most models do not use the score as an input, so a match's total mixes very different phases.
Analysts sometimes study xG in level game states only, or adjust for the score, to get a fairer view. Such adjustments are newer and less settled than xG itself.
When the chances come, in our own data
Chances rise through each half, highest just before half time and at the end, when trailing teams push and leading teams defend deep. Part of the rise is added time, which falls in those blocks.
Reading a match with game state in mind
Look at when the xG came, not only how much. An xG race chart shows it at a glance: a flat line after a goal, a steep one while chasing.
Questions
Do xG models know the score?
Most do not. That is why a team that leads early can end with less xG than a side that chased the game.
What is game state?
The score at a given moment, from one team's point of view: leading, level or trailing.
Sources
- John Knight: Introducing contexG (game state and xG)
- Opta Analyst: What is expected goals (xG)? · 2023
Checked 2026-10-28. Methods change: every figure here is dated to its source.
xG explains football; it is not a betting tip. 18+ · Please gamble responsibly.