The robot umps are here.
Major League Baseball’s competition committee on Tuesday afternoon approved the introduction of the automated ball-strike system, or ABS, for the 2026 regular season. Every team will begin next year’s games with two challenges of the home plate umpire’s strike zone, and a team will not lose one of its challenges when it gets the challenge right. When a challenge is issued, the umpire will review how a high-tech camera system called the pitch, and that determination will be final.
MLB has been testing ABS in Triple A since 2022, and tried out the system in major-league spring training for the first time in 2025. The system’s introduction for 2026 has been expected for months, ever since commissioner Rob Manfred said in June he likely would propose ABS to the committee. Manfred and MLB ultimately have control over the committee’s decisions; per the collective bargaining agreement with the players, the league office has six appointees on the 11-person committee, the players have four, and the umpires have one.
“The previous rule changes that have been adopted by the Joint Competition Committee have had staying power and created momentum for the game,” Manfred said in a statement. “We used the same process with ABS that started with listening to fans, conducting extensive testing at the minor league level, and trying at every step to make the game better. Throughout this process we have worked on deploying the system in a way that’s acceptable to players.”
Challenges can be issued only by the players directly involved with a given pitch: the pitcher, catcher and batter. Managers cannot issue one, and players are forbidden from receiving any help from others in issuing the challenge. The request has to be made immediately after the pitch.
In spring training this year, 288 games were played with ABS and they saw an average of 4.1 challenges per game, the league said in its news release. Calls were overturned 52.2 percent of the time, and challenges added 13.8 per seconds on average. Catchers had the greatest success overturning pitches at 56 percent of the time, compared to 50 percent for hitters and 41 percent for pitchers.
Full counts prompted challenges in spring training more than any other count. Players challenged least often on 3-0. But the higher leverage the count, the less successful the challenges were.
In its testing processes in the minors, MLB looked at an implementation of ABS on every pitch, but decided this challenge system, as it’s referred to, was the best choice.
At least one player appointee to the committee, however, opposed the rule change Tuesday.
“The vote of the players on the committee was not unanimous, which was reflective of the broad player sentiment,” the Players Association said in a statement Tuesday.
At the All-Star Game, MLBPA head Tony Clark expressed concern over teams getting the closest of calls reversed and wondered whether a buffer zone should be considered. Manfred said at the time that was not on the table.
There’s one change from the way MLB tested the system during spring training: Every team will have at least one challenge at the beginning of each individual extra inning that is played. So if a team has exhausted both of its challenges in the first nine innings, it will receive an extra one to start the 10th. But a team will not receive an extra one if it still possesses one or two.
The MLBPA reps on the committee have often voted against rule changes MLB has proposed during this CBA, which dates to 2022. Many of the changes Manfred has pushed through have worked out well, however, most notably the pitch clock, which was introduced in 2023. The union reps sometimes oppose changes not because they disapprove of the whole concept of a given rule, but because there are some parts of the rule they disagree with.
“The strong preference from players for the challenge format over using the technology to call every pitch was a key factor in determining the system we are announcing today,” Manfred continued in his statement. “I commend the Joint Competition Committee for striking the right balance of preserving the integral role of the umpire in the game with the ability to correct a missed call in a high-leverage situation, all while preserving the pace and rhythm of the game.”
(Top photo of an ABS challenge during the 2025 MLB All-Star Game: Matthew Grimes Jr. / Atlanta Braves / Getty Images)