Active Support Index (ASI)
metrics
tracking-data
Quantifying off-ball movement during pressure situations
Overview
A novel metric for quantifying off-ball movement during pressure situations, developed for the SkillCorner x PySport Analytics Cup (2025-2026).
The Problem
When a teammate is under pressure, what makes good off-ball support? We intuitively know when teammates “show for the ball” vs. hide from it. But can we quantify it?
The Solution
ASI measures how actively teammates support the ball carrier during pressure situations. It captures positioning, movement toward passing lanes, and availability as an outlet.
Data
- 10 A-League 2024/25 matches
- 7,063 pressure events
- 8+ million tracking data points from SkillCorner
Validation
ASI correlated strongly with physical performance metrics (r=0.74, p<0.001). Players who score higher on ASI tend to be the ones covering more ground and making themselves available. The metric appears to capture something real.