MLB Releases Results of Spring Training ABS Challenges

Overview of the Automated Ball-Strike System

Major League Baseball (MLB) has published the results from the Spring Training using the Automated Ball-Strike System (ABS). This year's data shows that 52.2% of ball-strike challenges were successful in overturning the home-plate umpire's original call. This marks a slight increase from the 50.6% success rate during Triple-A in 2024.

Implementation and Challenge Details

The ABS was utilized at 13 Spring Training parks, covering 19 home teams, and was in effect for approximately 60% of Spring Training games in 2025. Each team began with two challenges per game:

• Challenges were made by batters, pitchers, and catchers.
• The pitching team had a 54.4% success rate in overturning calls, while the hitting team achieved a 50.0% rate.
• Catcher challenges were notably more successful, with a 56% overturn rate compared to the 41% success rate for pitchers.

Impact on Game Duration and Challenge Patterns

During ABS games, 2.6% of called pitches were challenged. On average, challenges added 13.8 seconds to game time, which is an improvement from the 16.6-second average from Triple-A in 2024. With four challenges per game, this resulted in less than an additional minute of gameplay. The average duration of Spring Training games was 2 hours and 38 minutes, an increase of three minutes from the previous year.

It's interesting to note that players were more likely to challenge pitches in higher-leverage counts, although those challenges were generally less successful:

• Challenges in crucial counts like 2-2 or 3-2 pitches had a 44% overturn rate.
• Conversely, the first pitch of a plate appearance saw a 57% overturn rate.

The overturn rates also declined as games progressed, with 60% of challenges resulting in successful calls in the first three innings compared to lower rates in later innings.