During the Atlantic League All-Star Game on July 10, 2019, in York, Pennsylvania, home plate umpire Brian deBrauwere was seen wearing an earpiece while working behind Freedom Division catcher James Skelton of the York Revolution. This setup was part of ongoing tests for automated umpiring systems in baseball. Major League Baseball plans to expand these trials during spring training at 13 ballparks hosting 19 teams, potentially paving the way for robot umpires to be used in regular-season games as early as 2026. (AP Photo/Julio Cortez)
Major League Baseball (MLB) is gearing up to test automated strike zone technology, often referred to as "robot umpires," during spring training games in 2024. The trials will take place in 13 ballparks hosting 19 teams and could pave the way for implementing this system in regular-season games as early as 2026.
The Automated Ball-Strike (ABS) system has been tested in minor league games since 2019, but adjustments are still being made, particularly in how the strike zone is defined. Commissioner Rob Manfred expressed his interest in introducing the technology in 2026 but emphasized that it would require negotiation with the Major League Baseball Umpires Association. The current collective bargaining agreement with the umpires is set to expire on December 1, making these discussions a priority.
During a meeting with team owners, Manfred explained that the spring training test would help MLB assess player and team reactions to the challenge system. "We need feedback from both sides to determine the next steps," he said.
This year's Triple-A minor league season saw ABS implemented in two ways. For the first part of the season, robot umpires handled games solo in some series, while a hybrid challenge system with human umpires was used in others. By midseason, MLB adopted a fully challenge-based system. In this format, human umpires make the initial calls, but teams have a limited number of challenges to request ABS reviews. Teams retain challenges if the review overturns the umpire's call.
The current ABS determines strikes based on where the ball crosses a three-dimensional strike zone. Changes have already been made to better align the system with player expectations. For example, the top of the strike zone was raised to 53.5% of a batter's height, up from 51%, while the bottom remained fixed at 27%.
Manfred revealed that every team would have a chance to experience the ABS challenge system during spring training, ensuring players gain a solid understanding of how it works. While not every ballpark will use the system, the plan guarantees meaningful exposure for all teams.
The tests aim to address concerns from players and clubs, some of whom have questioned whether ABS can accurately and fairly interpret the complexities of the strike zone. MLB is striving to strike a balance between technological precision and maintaining the human element of umpiring.
The success of the spring training trials could determine whether robot umpires will revolutionize the game in 2026, marking a significant shift in how balls and strikes are called.
