ELKHART LAKE, Wis. (AP)Ty Gibbs overtook NASCAR Cup Series champion Kyle Larson on the final lap of overtime Saturday at Road America for his fourth Xfinity Series victory of the season.

The race featured a major wreck that impacted about a third of the 38-car field.

Larson, competing in an Xfinity Series event for the first time since 2018, was leading when Cole Custer’s brake failure resulted in a late caution flag that produced overtime.

The 19-year-old Gibbs, the grandson of team owner Joe Gibbs, chased Larson for much of the overtime session, passed him early in the final lap and remained in front the rest of the way for his third career road-course win. Gibbs’ winning margin was 0.858 seconds.

”This is just awesome,” Gibbs said. ”I can’t believe it. This is wonderful.”

Larson had decided to enter the Xfinity event to get more experience at Road America. He won the first two stages and was ahead for most of the race but couldn’t maintain the lead in that final lap.

”He did a really good job executing, and I didn’t,” Larson said.

Josh Berry finished third, Austin Hill fourth and Brandon Jones fifth.

The race was in its 25th of 45 laps when contact between Noah Gragson and Sage Karam started a wreck that involved 13 cars.

Gragson and Karam already had made contact a couple of times before the right side of Gragson’s car hit the left side of Karm’s vehicle, setting off a chain of events that altered the field.

Their Chevrolets eventually ended up sideways on the track as some cars managed to elude them while others got involved in multiple collisions amid a giant cloud of smoke. The Chevys of Landon Cassill and Myatt Snider both spun around on the track at one point. Brandon Brown had a major collision with Tyler Reddick.

”The 9 (Gragson) literally just drove into me in a straight line,” Karam said over the radio after the crash. ”He just hard-turned into me. What an idiot, man.”

Karam had more to say later on about Gragson.

”It’s ridiculous,” Karam said. ”I think he tried to take officiating or whatever in his own hands. You can’t be that heated when you’re driving a race care. Unfortunately, he let his emotions get the best of him today. I’ve seen that in him. He walks around like he’s like the big man on campus around here and everything, and he does stuff like that. Not a good role model.”

Gragson cited incidents both Saturday and in the past when Karam had initiated contact with him.

”I take responsibility and hate it for those guys, but we’re fighting to race for a championship here,” Gragson said. ”I’m really over getting run over.”

Brandon Brown climbed out of his car slowly and was down for a few minutes before getting himself up to undergo treatment after the wreck. He was treated at the infield care center and was released along with Brett Moffitt, Cassill, Snider, Karam and Reddick.

”I couldn’t really see anything until I saw the 48 when I plowed him,” Brown said. ”Just a real gut check. Lost my breath.”

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