Here are Major League Baseball's ABS firsts

The Automated-Ball Strike (ABS) Challenge System, powered by T-Mobile, got its first official use at the Major League level in 2026.

In light of the historical significance, MLB.com will be keeping a running list of regular-season and postseason ABS firsts -- beginning, of course, with the first challenge ever issued in a regular-season Major League Baseball game.

Regular season

First challenge

Date: March 25, 2026
Game: Yankees at Giants (4th inning)
Player: José Caballero (NYY), batter

The first official ABS challenge was issued by Yankees shortstop Caballero on a first-pitch called strike from Logan Webb. The call on the field was upheld.

First successful challenge/first call overturned for a strikeout

Date: March 26, 2026
Game: Pirates at Mets (3rd inning)
Player: Francisco Alvarez (NYM), catcher

The first successful ABS challenge was initiated by Alvarez, the Mets catcher, on a 3-2 pitch that was initially called a ball. The call on the field was overturned, as Freddy Peralta's fastball was in the zone, resulting in a strikeout of the Pirates' Oneil Cruz.

First successful challenge by a batter

Date: March 26, 2026
Game: Twins at Orioles (2nd inning)
Player: Matt Wallner (MIN)

With an 11.7% walk rate and a serviceable chase rate last season, Wallner is a pretty good judge of the strike zone. That paid off when Orioles starter Trevor Rogers dealt him a pitch that landed above the strike zone. It was initially called a strike, but Wallner challenged the call, which was overturned.

First challenge by a pitcher

Date: March 26, 2026
Game: Rangers at Phillies (8th inning)
Player: Zach Pop (PHI)

The only challenge by a pitcher on Opening Day came from the Phillies' right-handed reliever, who was certain his 3-2 pitch to the Rangers' Brandon Nimmo clipped the zone. Alas, the call on the field of a ball was upheld as the pitch did indeed land too far inside, resulting in a walk.

First successful challenge by a pitcher

Date: March 28, 2026
Game: Athletics at Blue Jays (8th inning)
Player: Hogan Harris (ATH)

Harris found himself in a jam in Toronto -- two runners on with no out in the eighth inning. His quick reaction to challenge this pitch -- called a ball to Ernie Clement -- turned a 2-1 count into a 1-2 count. Clement would end up flying out.

First call overturned for a walk

Date: March 26, 2026
Game: Twins at Orioles (4th inning)
Player: Josh Bell (MIN), batter

The Twins took four walks against the Orioles on Opening Day. That includes one that was confirmed by an ABS challenge. Once Rogers' 3-0 pitch against Bell was called a strike, Bell tapped his helmet to initiate a review that showed the offering missed up and away. Twins hitters challenged three calls on Opening Day and won all three.

First call overturned to end a game

Date: April 1, 2026
Game: Rangers at Orioles
Player: Samuel Basallo (BAL), catcher

With the Orioles leading the Rangers, 8-3, with two outs in the ninth, right-hander Albert Suárez delivered an elevated 1-2 fastball to Texas’ Evan Carter. The pitch was initially called a ball, but young Orioles catcher immediately challenged. The review showed that the pitch did hit the outside corner, resulting in a strikeout and the Major League’s first game-ending ABS challenge.

Postseason

First challenge/first successful challenge by a batter

Date: Sept. 29, 2026 (NL Wild Card Series, Game 1)
Game: Phillies at Braves (2nd inning)
Player: Ozzie Albies (ATL)

Albies became the first player to challenge a pitch in the postseason, doing so in the second inning of Game 1 of the NL Wild Card Series against the Phillies. The Braves second baseman tapped his helmet to challenge a 1-0 called strike on a fastball from Philadelphia lefty Jesús Luzardo. The review showed the pitch was 2.5 inches out of the zone, and the call was overturned. It proved to be pivotal: Albies drew a walk and came around to score, tying the game at 1-1.

First call overturned for a strikeout

Date: Sept. 29, 2026 (AL Wild Card Series, Game 1)
Game: Red Sox at Yankees (1st inning)
Player: Austin Wells (NYY), catcher

Yankees starter Cam Schlittler dominated the Red Sox over 6 1/3 scoreless innings in Game 1 of the AL Wild Card Series, striking out 10. On at least one of those strikeouts, he got some help from his catcher. When a 1-2, 97.7 mph cutter from Schlittler to Wilyer Abreu appeared to catch the outside edge but was called a ball, Wells challenged the pitch. He was right: The call was overturned for strike three, ending the first inning.

First call overturned for a walk

Date: Sept. 29, 2026 (AL Wild Card Series, Game 1)
Game: Red Sox at Yankees (4th inning)
Player: Amed Rosario (NYY), batter

The Yankees pulled off another big challenge later in Game 1, when Amed Rosario took a borderline cutter from Red Sox starter Payton Tolle on a 3-2 count. Rung up on strikes by the home-plate umpire, Rosario tapped his helmet on his way to first base, confident in his challenge. He proved to be correct: The pitch was 1.8 inches outside, putting Rosario aboard on a walk.

First call overturned to end a game

Date: Sept. 30, 2026 (NL Wild Card Series, Game 2)
Game: Phillies at Braves, 10th inning
Player: J.T. Realmuto (PHI), catcher

It's hard to imagine a much more significant overturn than the one that ended Game 2 of the 2026 NL Wild Card Series in Atlanta. With two Braves on base in a 4-3 game in the bottom of the 10th, Phillies righty Andrew Painter nipped the inside edge on an 0-2 fastball to pinch-hitter Dominic Smith. Realmuto challenged the ball call, which was overturned to strike three to seal a dramatic win for Philadelphia and extend the series to a third game.