Bayne was fourth on a restart with one lap left in the 20-lap segment, but he was able to split the front row of Ryan Blaney and leader Chase Elliott to take the lead.
Replays showed his No. 6 Ford beat Elliott to the finish by 0.004 seconds, and Bayne credited a push by teammate Ricky Stenhouse Jr. to helping him win.
“I don’t think I was sweating until Lap 19 coming off Turn 2, there was a tiny hole, and we got a good restart,” Bayne told FS1. “I pushed (Blaney) out past the start-finish line.
“Our Ford was good in clean air, but all we had was a restart. They kind of fanned out, I got a run and saw a little hole and somehow we made it through without a car getting beat up. Ricky came and gave me a huge push. Without that, we probably don’t win the race. It’s really nice to have a teammate who will choose to work with you when it might not be in his best interest.”
NASCAR black-flagged Blaney for jumping the restart, putting him at the rear for the second 20-lap segment.
Bayne will be joined in Saturday night’s Sprint All-Star Race by the winners of the other two segments of the Showdown. Two drivers also will transfer via the fan vote.