2026 MLB Automated Ball-Strike (ABS) Challenge Analysis

An automated ball-strike (ABS) challenge lets the batter, pitcher, or catcher contest a called ball or strike, which is then re-judged by the automated strike zone. Each team starts a game with two challenges; a successful (overturned) challenge is retained, a failed one is spent. Teams that run out in regulation get one additional challenge for each extra inning they begin without one.

All figures below are for the 2026 MLB regular season.

Challenges by Position

  • Who challenges, and how often the call is overturned.
Challenges by Position
Pos Chal Overturned Overturn%
catcher2296136359.4
batter206497847.4
pitcher923234.8
Total4452237353.3

By Inning & Challenges Remaining

  • Based on how many challenges the team had remaining when it challenged in each inning.
By Inning & Challenges Remaining
2 Challenges Left 1 Challenge Left
Inn Chal OT OT% Chal OT OT%
140724560.2161381.3
236121960.7231252.2
334219356.4673755.2
437619551.9805568.8
535421059.31076056.1
638420152.31407452.9
737620955.617810357.9
831213643.625413352.4
930010936.329113345.7
1011218.2542648.1
112150.011545.5
12005240.0
1300100.0

By Ball-Strike Count

  • Count the pitch was thrown in (before the pitch).
By Ball-Strike Count
Count All Challenges As Batter Defense (C/P)
Balls Strikes Chal OT% Chal OT% Chal OT%
0096758.937951.258863.9
0149157.820242.628968.5
0224452.511444.713059.2
1042857.919962.322954.1
1142355.123947.718464.7
1236049.217341.018756.7
2018755.17965.810847.2
2129151.215441.613762.0
2240548.420039.020557.6
306258.12462.53855.3
3118450.08858.09642.7
3241038.321336.619740.1
Become a Stathead & surf this site ad-free.

By Baserunners

  • Base-occupancy state before the challenged pitch.
By Baserunners
Baserunners Chal Overturn%
Bases empty231055.1
Runner on 1st87053.1
Runner on 2nd35253.4
Runner on 3rd10046.0
Runners on 1st & 2nd38153.3
Runners on 1st & 3rd14650.7
Runners on 2nd & 3rd10448.1
Bases loaded18941.3

By Leverage Index (LI)

  • Leverage index (LI) measures how much the game situation -- inning, score, outs, baserunners -- can swing on the play. 1.0 is an average situation; higher means higher stakes.
By Leverage Index (LI)
Leverage Chal Avg LI Overturn%
0.0 - 0.5 (very low)13310.2351.2
0.5 - 1.0 (low)12930.7656.7
1.0 - 1.5 (medium)7761.2351.7
1.5 - 2.5 (high)6781.9056.6
2.5+ (very high)3743.7246.5

By Month

  • Challenge rates by month -- per game (both teams) and overturn rate, split by who challenged.
By Month
Total Batters Catchers Pitchers
Month G Chal/G OT/G OT% Chal/G OT/G OT% Chal/G OT/G OT% Chal/G OT/G OT%
March763.762.0454.21.760.8749.31.911.1359.30.090.0442.9
April3924.192.2353.31.930.8845.42.171.3260.80.090.0441.2
May4194.062.1151.91.890.8947.32.091.1957.20.080.0220.6
June1814.552.5556.02.101.0750.92.351.4360.90.090.0447.1

Distribution of Challenges per Team-Game

Distribution of Challenges per Team-Game
Challenges Team-Games % of Team-Games
01989.3%
154725.6%
268332.0%
343120.2%
41908.9%
5532.5%
6231.1%
780.4%
930.1%

Strike-Zone Heatmap

Pitch location from the umpire's view. The bordered 3×3 grid in the middle is the strike zone. The four corner cells are out of the zone — each one covers all the missed pitches beyond that corner, sweeping along the two zone edges it borders (as the arrows show), not a single spot.

  • First map: overturn rate (top) and challenge count (bottom), darker = more often overturned.
  • Second Map: where batters tend to challenge. -- number of challenges (top) and share of total (bottom)
  • Third Map: where pitchers and catchers tend to challenge. -- number of challenges (top) and share of total (bottom)

Overturn rate

43.1%376
50.0%348
63.6%382
69.2%104
59.2%250
54.1%229
52.1%163
55.9%524
55.5%308
49.8%520
49.8%594
52.9%654

Batter challenges

1628%
1748%
1397%
322%
1025%
1055%
784%
23111%
1377%
26113%
29714%
34617%

Catcher / pitcher challenges

2149%
1747%
24310%
723%
1486%
1245%
854%
29312%
1717%
25911%
29712%
30813%

Challenges by Team

  • Each team's own challenges (with role splits) and the challenges their opponents made against them

Challenges by Player

By Home Plate Umpire

  • Challenges of the home plate umpire's ball/strike calls. A high overturn rate means more of the challenged calls were reversed. Sortable.

Most Overturned Challenges, By a Team in a Game

  • Top 25 team-games by overturned challenges.

Earliest Lost Final Challenges

  • Failed challenges that left a team with no challenges, ordered by how early in the game they happened. Top 25.

Lost Both Challenges in One Plate Appearance

  • Players who challenged twice in the same at-bat and were upheld both times -- two challenges burned in one plate appearance.

Most Games Losing Both Challenges

  • Players who lost both of their team's regulation (inning <= 9) challenges in the same game, by how often. Top 25.

Highest Leverage Challenges

  • The 25 challenges made in the highest-leverage situations. LI 1.0 is an average situation.

Best Challenges by Catcher/Pitcher

  • Overturned ball-to-strike challenges, closest to the center of the zone -- the most obvious missed strikes they caught. Top 25.

Best Challenges by Batter

  • Overturned strike-to-ball challenges, farthest outside the zone -- the most obvious missed balls they caught. Top 25.

Worst Challenges by Catcher/Pitcher

  • Upheld ball challenges (the call stood), farthest outside the zone -- they challenged obvious balls. Top 25.

Worst Challenges by Batter

  • Upheld strike challenges (the call stood), closest to the center -- they challenged obvious strikes. Top 25.