Major League Baseball has been testing a new replay system in the Arizona Fall League, and Thursday brought the first overturned call, according to Cory DiBenedetto of Gammons Daily.
The call came in the top of the first inning. Tampa Bay Rays farmhand Ryan Brett attempted to steal second base, but was thrown out by the catcher. Upon video review, however, it was judged that Brett's foot hit the bag ahead of the shortstop's high tag. The call was reversed by home plate umpire Sean Barber, and Brett was ruled safe. The entire process took about 70 seconds, from the moment that Brett was called out until the moment that Barber changed the call.
The AFL has been testing out the new replay system all week. Replays are reviewed by an off-field judge with access to multiple video angles, and, when a manager challenges a call, the on-field umpire is given a headset with which to receive the official judgment from the off-field authority. Rob Neyer detailed the first two days of video replay here and here.
Brett's stolen base: