What is baseball’s Automated Ball-Strike Challenge System (ABS)?: Quick Facts

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An umpire stands in front of the scoreboard at Camelback Ranch, which displays an ABS Challenge System review showing a pitch called a ball during a Dodgers and White Sox game.

Jesus Sanchez of the Miami Marlins signals for an ABS review during a 2025 spring training game, holding a bat and wearing a blue jersey with a blurred crowd in the background.

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