Watch Yankees SS Make MLB's 1st-Ever ABS Challenge During Opening Day vs. Giants

New York Yankees shortstop José Caballero became the first MLB player to use the Automated Ball-Strike Challenge System in a regular-season game during the team's Opening Day clash with the San Francisco Giants on Wednesday.

Caballero challenged a strike call on Giants starter Logan Webb's pitch in the fourth inning of the game, although the call was upheld.

Following the unsuccessful challenge, the Yankees had one challenge left for the remainder of the game.

Each team starts with two challenges per game under the new ABS system, although they're allowed to retain their challenge if it is successful.

Yankees manager Aaron Boone previously revealed that he doesn't want his players to take a conservative approach with challenging calls.

"The thing we've found with this where it's been used is, people don't challenge enough," Boone said on Feb. 18, per Greg Joyce of the New York Post. "When you first hear about it, the natural reaction or tendency is, 'I got to save them.' Then you end up taking them home. Games are won and lost in the second, third and fourth inning all the time. So we want our guys to be good at it, we want them to be disciplined, but we also want them to be aggressive with it."

Before ABS was introduced for MLB teams to use in the regular season, the system was tested in the minor leagues starting in 2022. It was also utilized in MLB Spring Training ahead of last season before gaining approval from the Joint Competition Committee in Sept. 2025.

As for Caballero, he's entering his first full year as a member of the Yankees after they acquired him in a July 2025 trade with the Tampa Bay Rays.