Busch pulled off an amazing recovery after being nudged by Jimmie Johnson midway through the race and also survived a multicar crash in the late going that forced a green-white-checkered finish.
He passed Stewart on the final turn of the last lap, finishing 0.01 seconds in front to take the preseason Sprint Cup tuneup contest.
Among the race's three crashes was one in which Jeff Gordon flipped upside down and slid hundreds of feet before emerging from the wreck unhurt.
Denny Hamlin rounded out the Top 5.
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