Blue Notes · Umpire Grade2026-07-21
DET @ CHC
Home plate: Nick Mahrley
“The zone had wings tonight.”
Umpire Grade
87.4% accurate
Run Favor
runs, DET
ABS Overturns
of 1 reviewed
What this shows — how Nick Mahrley called the 198 pitches that were taken (no swing), graded against the tracked rulebook strike zone. He got 173 right. Below, only his misses are plotted, alongside every pitch the ABS (Automated Ball-Strike System) reviewed on a challenge.
The zone, as he called it
strike called ballball called strikeABS overturnedABS upheld
The calls that moved the game
- 1-0.39▼3 · 2-2 ball called strike
Carson Kelly vs Ty Madden - 2+0.39▲7 · 2-2 strike called ball
Dillon Dingler vs David Peterson - 3+0.39▼8 · 2-2 strike called ball
Seiya Suzuki vs Jake Rogers
Run impact from the count run-value table: a missed strike three is worth far more than one on 3-0.
ABS — the Automated Ball-Strike System
1 pitch went to the robots · 1 overturned (ump overruled) · 0 upheld (ump confirmed). This is the ABS system’s own measurement — Hawk-Eye optical ball-tracking, not our model.
- 1Carson Kelly — ump said strike, robot ruled ball: overturned.
Our tracked-rulebook zone matched the ABS ruling on 0 of 1 — a zone-definition gap (ABS grades a standardized, height-based zone), not our error.