Keselowski passed Busch on Lap 258 after hounding his rear bumper for most of the 130-lap stage. Busch led 123 laps of the stage
Playoff driver Denny Hamlin finished the stage in 13th after he was caught speeding on pit road during the Stage 1 break. Hamlin stayed on the lead lap despite Busch trying to pass him for much of the closing laps of the stage.
Hamlin held up Busch enough for Keselowski to stay within reach and eventually pass Busch.
Keselowski has led 54 laps.
There were no cautions in the stage.
The race is scheduled to end after 500 laps.