Expected Goal Involvement (xGI)
Expected goal involvement adds a player's expected goals to his expected assists, giving a single number for the chances he finished and the chances he created for others.
What it means
The two components are mutually exclusive by construction, since a player cannot assist his own shot, so the sum is a clean total of a player's direct involvement in chance creation and conversion.
Why it matters
It gives a single comparable figure for attacking contribution, which is useful when comparing players in different roles whose value is split unevenly between scoring and creating.
Where it is used
Forward and midfielder comparison, and any assessment of a player's attacking output where one component alone would misrepresent the role.
Where it misleads
It flatters set-piece specialists, whose delivery volume inflates the assist component. It cannot capture value delivered in the second or third pass before a chance, and it says nothing about a deep midfielder's progression work.
Key points
- The sum is clean because the two components cannot overlap.
- Report the components separately to recover the player's role.
- Set-piece involvement should be split out before comparison.
- It excludes value created two passes before a shot.
- Low values for defensive players are expected and not a criticism.
- It is an attacking metric and does not measure defending.
Goal involvement is a total rather than a profile, and the profile is recoverable only by printing the two components beside it.