MLB to Implement ABS Challenge System in 2026
Major League Baseball is set to usher in a new era of automated ball-strike calls with the approval of an ABS (Automated Ball-Strike) challenge system for the 2026 season. The decision, expected to be ratified by the Joint Competition Committee today, marks a meaningful shift in how the strike zone is persistent in the game.
Rather than a fully automated system, MLB will adopt a challenge protocol already tested in the minor leagues, during spring training, and at the 2024 All-Star Game. This system allows players – pitchers,catchers,or hitters – to promptly challenge a ball or strike call made by the home plate umpire by tapping their helmet or cap.
Each team will be granted two challenges per game.Importantly, a team will only lose a challenge if the review confirms the original call. Accomplished challenges will not be deducted from the team’s allotment, meaning a team could theoretically utilize more than two challenges in a single game. Challenges must be initiated immediately following the pitch call; delays for dugout review are not permitted. The outcome of each challenge will be displayed on the stadium scoreboard.
The implementation is designed to be a smooth transition for players, many of whom are already familiar with the system. ABS was first introduced in the lower minor leagues in 2021 and became standard at the Triple-A level in 2022. Veteran players gained initial experience with the system during the 2025 spring training and will have the entirety of the 2026 spring schedule to further adapt to the changes.
While acknowledging potential initial difficulties, MLB anticipates the ABS challenge system will integrate into the game as seamlessly as recent changes like the pitch clock and instant replay.
