Lucas Carrasquilla
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Probability and football. Published in 2026.

Decision safety in football passing

A reproducible metric from probabilistic option sets

Lucas Carrasquilla, José Alejandro Guerrero-Vargas and Pedro Wightman

International Journal of Sports Science & Coaching, 2026

Pass diagram on a green pitch showing the passer, the receiver, two defenders, the pass distance and the distance to goal.
The spatial features behind the completion model. Every visible teammate is scored as a possible receiver.

The question

A completed pass records what happened. Assessing the choice also requires the alternatives. StatsBomb 360 freeze frames make it possible to reconstruct the passing options visible at the moment of release.

What the analysis finds

Decision safety and opportunity-adjusted risk-taking locate the chosen pass within its option set, using two normalisations of the same quantity. Most of the variation is situational: differences between players account for 4.4% of the variance in decision safety, rising to 9.8% where the option set is most heterogeneous.

What the result means

These measures describe safety, not overall decision quality. Safer passers create fewer chances, r = -0.34 against expected assists per pass, and the apparent link between attacking-third risk and possession expected goals is accounted for by the shot-assist pass itself.

Data and method

An XGBoost model estimates completion probability from situational features, without player identity. It is evaluated with match-grouped cross-validation and applied to every visible alternative. The analysis covers passes with a usable freeze frame and a recorded recipient.

From the paper

Histogram of player-mean decision safety coloured by position, with the mean at 0.735.
Player-mean decision safety for players with at least 25 passes, by position.
Intraclass correlation of decision safety and opportunity-adjusted risk-taking rising from about 2% to about 10% as option-set heterogeneity increases.
How much of each measure belongs to the player rather than the situation, by how different the available options were.