The new computerized system is being tested during spring training, leading to a series of challenges from players who don’t know the strike zone quite as well as they think.

Though this hybrid umpire system won’t make its way to regular season major league games in 2025, player and fan reactions during this crucial trial period could determine whether or not it becomes a regular staple in games.

A computerized system that calls balls and strikes is being tested during Major League Baseball spring training exhibition games starting Thursday after four years of experiments in the minor leagues.