A spring training’s worth of the automated ball-strike challenge system: Are robot umps coming to MLB?

The New York Yankees’ Jazz Chisholm Jr. showed how to confidently use the still-in-trial Automated Ball-Strike System (ABS) in a Spring Training game against the Boston Red Sox last week – so confidently that he started jogging to first base before a decision was even made.

The New York Yankees’ Jazz Chisholm Jr. showed how to confidently use the still-in-trial Automated Ball-Strike System (ABS) in a spring training game against the Boston Red Sox last week – so confidently that he started jogging to first base before a decision was even made. In the bottom of the sixth inning, with a runner on base, one out and facing a full count, Chisholm had a third strike called on him by the home plate umpire, which he thought was below the strike zone. The outfielder immediately tapped his helmet and started heading for first. To any baseball fans who haven’t been watching this season’s spring training games, it would have been utterly confusing. Major League Baseball (MLB) has been testing the ABS challenge system during certain 2025 spring training games to explore its suitability for possible full-time use in the future and to identify further changes in minor league game use. The minor leagues began testing a full ABS system in 2021 before it reached the Triple-A level, one step below the majors, in 2022. This full system was what many called “robot umps,” where a video system replaced human umpire calls entirely. Part of that early trial and error period revolved around defining the ABS strike zone to ensure the system accurately adjusted to each batter’s strike zone based on their height.