Ross Chastain had his doubts, but a late-race pit strategy call turned into a career-best finish in Sunday‘s Cup Series at Nashville.

LEBANON, Tenn. — Ross Chastain had his doubts, but a late-race pit strategy call turned into a career-best finish in Sunday‘s NASCAR Cup Series Ally 400 at Nashville Superspeedway.

Chastain‘s crew chief, Phil Surgen, made the call to stay out following a caution on Lap 218 of the 300-lap race at the 1.33-mile track and Chastain quickly lost the lead to eventual race winner Kyle Larson after the restart with 78 laps remaining. But the key caution came later in the race, the yellow flag flying for the final time on Lap 227 when Chase Briscoe clipped the wall after a brake failure.

Surgen rolled the dice and made the split decision to bring the No. 42 Chip Ganassi Racing Chevrolet in for service, giving up a top-five position on the race track.

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That‘s also where Chastain had his doubts, but he also didn‘t realize they could make it on fuel through the end of the race while others were cutting it close.

"It was humbling," Chastain said after the race. “They know better than I do. They also knew we could make it to the end. I wasn‘t thinking that far ahead. We would have had to pit under green there, even if we stayed in the top four or five. They know what they‘re doing. I am sorry that I doubted them.”

The end game worked out well for Chastain, rocketing up to a second-place finish in the final 68 green-flag circuits with fresh tires and plenty of gasoline.

It was a lesson learned for Chastain.

“Heat of the moment in the car,” Chastain said. “It‘s really hot, I‘m sweaty and tired and I‘m like, man, we‘re running third and we‘re gonna give this up. I need to just drive.”

The result also served as Chastain‘s second top five of his Cup Series career, following a fourth-place finish at Circuit of The Americas in May. The reaction from the 42 crew was a special moment for Chastain, as well.

“Positive like the guys got goosebumps driving up through the field,” Chastain said. “I get out of the car and they were like, 'man, we haven‘t had that in a long time.‘ I hadn‘t, either.”

As Larson and Hendrick Motorsports continue to tally top-five results, Chastain was able to pass William Byron in the closing laps to seal his career-best performance in NASCAR’s premier series.

For Chastain, the finish wasn‘t a fluke, but more of a sign of things to come.

“That‘s where we belong — second place,” Chastain said. “It‘s just going to build confidence and all. It‘s like we‘re doing the right things.”