MLB 2026 · Automated Ball-Strike Challenge System
Every called pitch is now challengeable. Here is the data.
A season of Hawk-Eye tracking, run-expectancy modeling, and a win-probability challenge engine — built to answer one question: when is a challenge actually worth it? Explore the numbers below, or read the full story.
643 games · 190,813 pitches · 2026-03-25 to 2026-05-13
The core relationship
A challenge is geometry.
The further a pitch sits from the zone edge, the more certain the overturn. Near the edge it is a coin flip — and that is exactly where a catcher’s eye and the game situation decide whether to spend a challenge.
Explore the data
Each surface is a thing you can poke at. Want the narrative and the methodology instead? Head to the writeup.
The zone
Where umpires miss, and how the overturn rate collapses as a pitch nears the edge.
Explore →Catchers
Each catcher's measured perception sharpness and how often their challenges land.
Explore →Umpires
Miss rates by zone region, and who gets challenged and overturned most.
Explore →Teams
Net challenge value, wasted challenges, and the runs each team leaves on the table.
Explore →Decision explorer
Pick a game state and see the confidence you need before a challenge is worth it.
Explore →