As the 2025 MLB season begins Thursday, this Opening Day may very well be the last in which balls and strikes are determined solely by the human eye.
MLB’s automated ball-strike system (ABS) was used in roughly 60% of spring training games across 13 ballparks for the first time, after years of testing in the minor leagues. The technology was not used to call each pitch, but instead as a basis to challenge the calls made by umpires.
Results from spring training show that 52.2% of ball-strike challenges resulted in a successful overturn of the home-plate umpire’s original call, which is up from 50.6% when the technology was used in Triple-A in 2024. Teams started games with two challenges apiece and lost them if the umpire’s call was confirmed. Batters, pitchers, and catchers were the only ones allowed to challenge.
MLB commissioner Rob Manfred has been a supporter of ABS and has previously suggested it could be used in the majors in 2026. Still, MLB appears far away from removing human officials in favor of 100% “robot umpires” anytime soon—or ever.
The technology will not be implemented at any point during the 2025 major-league season, but it will continue to be used in the minors.
Tech Time
Adding ABS would be the latest tech advancement for MLB, which implemented the pitch clock in 2023, in part leading to a big decrease in overall game times.
Last season, average game times shrank to two hours, 36 minutes, which marked a four-minute reduction from 2023 and MLB’s lowest figure since 1984.
