Saw a hitter, catcher, or pitcher tap their helmet after a pitch and wondered what just happened. Here’s a clear guide to MLB’s ABS challenge system, including who can challenge, how many challenges ...

On any given pitch, both teams are eligible to initiate an ABS challenge. But not every player on the field has the right.

PHOENIX — For more than 150 years, the game of baseball has relied on humans behind home plate to call balls and strikes. This spring, for the first time in Major League history, players will be able ...

Similar to regular instant replay, the goal of the ABS challenge system is to correct the most egregious missed calls, though we will inevitably see some ticky-tack replays as well. More than a few ...

The Automated Ball-Strike Challenge System lets players appeal umpire calls, adding accuracy and strategy to the game.