The Trackhouse Racing Chevrolet driver took the lead after the final set of green flag pitstops, and narrowly avoided a 23-car pileup in the closing laps. Daytona 500 glory was in sight, but the battle wasn't over just yet.
William Byron (Hendrick Chevrolet) took over at the front when racing resumed after a brief red flag with four of the 200 laps remaining, but Chastain mounted a massive charge coming to the white flag.
With Alex Bowman (Hendrick) pushing Chastain, Byron moved up the track to block. At the same, Austin Cindric and Corey LaJoie got crossed up on the inside lane.
Chastain saw an opportunity and tried to shoot the gap up the middle but there just wasn't enough room for all three cars, with Chastain and Cindric sent spinning into the infield as the final lap began. The caution flag immediately followed and Byron was declared the race winner.
Despite the disappointment of being classified 21st after leading 14 of the final 20 laps, and missing out on a fifth Cup Series victory, Chastain confirmed he was satisfied with the showing.
"I am [satisfied]," said Chastain. "To learn the fuel saving game and really get aggressive and match these guys, so that we can pit when we need to...
"I have burned up too much fuel in the past couple of races and to put ourselves in position on the final pitstop to come out with the lead, cover the other OEM [Ford] when they caught up to us, and just work with some legends of the sport, and have control over the race there at the end.
"I really do feel content. It’s weird to say it, but we did everything right."
Source: Autosport