How does the ABS challenge system work and how will it impact games?

KANSAS CITY, MO - MARCH 30: Maikel Garcia #11 of the Kansas City Royals signals for an ABS challenge against home plate umpire Alex Tosi in the fifth inning during the game between the Minnesota Twins and the Kansas City Royals at Kauffman Stadium on Monday, March 30, 2026 in Kansas City, Missouri. (Photo by Mikayla Schlosser/MLB Photos via Getty Images) | MLB Photos via Getty Images Over the first week of games, you may have noticed pitchers, catchers, and hitters tapping their head after a pitch, signaling for a review. After six years of testing in the minors, MLB has implemented an Automated Ball Strike (ABS) challenge system that allows players (not coaches) to ask for a replay review of balls and strikes.

Through the first week of games, the new wrinkle has brought added excitement and accountability to umpires. So how does it work? Human umpires still call balls and strikes behind home plate.

But if a pitcher, catcher, or hitter wants to challenge the ruling, they have to tap their head. Each team will be given two challenges during the first nine innings, with one challenge in each extra inning. Each team gets an additional challenge in the tenth inning.

If that challenge is used, they’ll receive another in the next inning; if not, it carries over The home plate umpire will announce the challenge, and the replay will be displayed on the ballpark video board. It should take no more than 15 seconds for the Automatic Ball Strike ruling to be issued. If the call is confirmed, the challenging team loses its challenge, but a team with a successful challenge will retain its challenge.