Erik Jones was leading on the final lap but the drivers behind him were getting antsy to make a move. Kyle Larson moved to the top lane to get around him and Jones followed him in an attempt to block.
Chastain, who was running third on the last lap, elected to remain on bottom lane and when those around darted up the track, he stayed low and held off Austin Dillon by 0.105 seconds to earn his second career win and second this season.
It’s also the Trackhouse Racing driver’s second win in the last five races for the team.
“Holy cow. I’m always the one going to the top too early and making the mistake,” Chastain said. “With eight to go, I was like, ‘No I’m not going up there. I’ll just ride the bottom. I’m not going to lose the race for us.’
“I have no idea [what happened]. They kept moving out of the way!”
Asked what he thought was possible joining Trackhouse this season, Chastain said: “Justin Marks [team co-owner] and what he laid out for us was ambitious, I had no idea what to expect other than I’d have my group from last year.
“They were believing in us. We had a lot of races open [for sponsorship] to start this year, they’re almost all filled now.”
Race winner Ross Chastain, TrackHouse Racing, Moose Fraternity Chevrolet Camaro
Photo by: John Harrelson / NKP / Motorsport Images
Jones, dejected, said he wished he had made a different decision on the final lap.
“That last lap, right? I’ve been close here so many times,” he said. “I felt pretty good, but that top line was getting momentum. Looking back, I wish I’d stayed on the bottom.
“I tried to defend [against Larson]. It is what it is, just trying to win the race.”
Kyle Busch also profited from the mistakes ahead to grab third place ahead of Larson in fourth and Martin Truex Jr in fifth.
Despite leading the final lap Jones could only manage a lowly sixth place in the circumstances, in front of Chase Elliott, who continues to lead the drivers’ championship even without finding that overdue first win of the season.
Michael McDowell produced his best result since the Daytona 500 with eighth place, as Alex Bowman and Kevin Harvick completed the top 10.
Richmond winner Denny Hamlin, who had been running in the front group late in the race, was forced to pit with three laps remaining because he was low on fuel and finished in 18th place.
NASCAR Talladega – race results