This spring, a different kind of prospect will be under the microscope in Clearwater. It doesn’t have a fastball, it doesn’t take batting practice, and it definitely won’t be signing autographs. But it might just change baseball forever.
When the Phillies open their Grapefruit League schedule on Saturday, they’ll be part of Major League Baseball’s biggest technological experiment yet: the Automated Ball-Strike System.
For the first time, big leaguers will get a real taste of the ABS challenge system, which will be used in 60 percent of spring training games across Florida and Arizona. That includes 27 of the Phillies’ 31 games. The umpire will still call balls and strikes, but if the batter, catcher, or pitcher doesn’t like a call, they can instantly challenge by tapping their hat. No replay reviews. No waiting. The correct call will appear on the scoreboard in seconds.
Phillies manager Rob Thomson has already thought through how to handle it. His preference is to let the catcher or batter make the call, since they have the best view of a pitch’s final movement. The team will meet Friday to discuss their strategy, but Thomson doesn’t plan to be overly tactical about it in the spring. If anything, he’ll encourage players on the roster bubble to use it, which makes this an intriguing subplot in camp.
The backup catcher competition between Garrett Stubbs and Rafael Marchán could be influenced by who manages the challenge system best. A strong showing behind the plate—and a few successful challenges—might tilt the decision.
Major League Baseball isn’t implementing ABS in the regular season just yet. Commissioner Rob Manfred has made it clear that the system won’t be used before 2026. Before any final decision is made, Triple-A will experiment with the challenge system for an entire season in 2025, giving the league additional data to analyze.
In previous minor league trials, challenges lasted about 17 seconds, with an overturn rate of roughly 50 percent. On average, teams used about four challenges per game. League officials believe the system offers the best balance, keeping human umpires in control while allowing players to correct obvious mistakes. Catchers also favor it, since it preserves the art of pitch framing rather than removing it entirely with a fully automated system.
For those eager to see the challenge system in action before the Phillies get their turn, the first ABS game of the spring will take place Thursday when the Dodgers and Cubs square off at Camelback Ranch.
So get ready. Robo-umps have arrived, and the countdown to baseball’s next big debate is officially underway.
