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Kyle Larson and his Chip Ganassi Racing team needed a break, and it came with two laps to go.

Running second to a dominant Martin Truex Jr. and itching for fresh tires and a shot at victory in overtime, Larson got it when Derrike Cope's car hit the wall, bringing out the seventh yellow flag of the night. Larson grabbed the lead on pit road and sailed to the victory.

"I guess we stole the win, I guess you could say, or our pit crew, I felt like, stole the win because they got me off as the leader," Larson said.

The victory was his fourth of the season, tying Truex for the most this year.

"I'm really pumped for the playoffs, we've got a really good shot at the championship," Larson said. "I've got the greatest team out here and definitely the best pit crew. They were money all night long to gain spots. This win is a huge congrats to them."

And to the 58-year-old Cope, who was starting his 13th race of the season and hasn't finished better than 31st. He was 38th at Richmond.

Truex, who clinched the regular-season NASCAR Cup title last week, had the race easily in hand until Cope crashed with under four laps remaining. Truex then wrecked in overtime while racing with Denny Hamlin for position. The sequence cost him his fifth win of the season.

"A caution for a guy who shouldn't even have been out there," Truex said about Cope. "It's kind of ridiculous."

Dale Earnhardt Jr. was officially eliminated from the playoffs with a 13th-place finish. He's retiring at the end of the season, and has never won a Cup title. Earnhardt stayed out during late green-flag pit stops, briefly assuming the lead with 66 laps to go, but the caution that could have made the strategy pay off never came.

"That's what we needed at the moment, and we didn't get it," Earnhardt said. "It was the only shot we had."

Truex will still start the 10-race playoff stretch as the favorite to win the championship because he earned the most bonus points during the regular season. He and his Furniture Row Racing team were presented with the regular-season championship trophy.

The reward is a slew of bonus points, but Truex feigned a smile because he'd have preferred to have the race winning trophy, too.

"Tonight is a little tough, it's a little hard to be excited," he said.

He's also got to watch over his shoulder for Larson, who now has a nice bit of a momentum going into the opening round of the playoffs at Chicagoland.

The Richmond victory was Larson's first on a short track in the Cup Series.

"This has been a dream season for me, and we still have a long way to go," Larson said,

Chaos erupted with 140 laps remaining because an ambulance clogged the entrance to pit road as cars headed to their stalls. When traffic bottlenecked, Matt Kenseth ran into the car in front of him, and his contending car was knocked out with a crumpled hood.

"I saw an ambulance sitting there," Kenseth said. "It was an accordion effect and I just couldn't get stopped."

The incident could have knocked Kenseth out of the playoffs had there been a first-time winner, but Larson fixed that, allowing Kenseth, Chase Elliott and Jamie McMurray to make the 16-driver field as the only non-winners.

Joey Logano and Clint Bowyer, both needing a victory to advance, also suffered damage in the ambulance incident. Logano ran in the top 10 for much of the night, and Bowyer got up into the mix a few times, but Logano's hope to strike lightning never quite materialized.

"It's happened to us a few times at Richmond that we didn't have a winning car and we won," he said. "We almost did it again."

Logano finished second, and Bowyer was 24th.

Logano did win here in the spring, but the result was "encumbered" by NASCAR when Logano's car was found to have an illegal rear end. Under series rules, Logano was allowed to keep the victory, but it no longer guaranteed him a spot in the playoffs. He also lost playoff points.

LURKING JIMMIE: Seven-time series champion Jimmie Johnson finished eighth, and is feeling upbeat after a struggling summer.

"Honestly, over the years and through the various challenges we've faced, I just think the tracks in the spring and the tracks in the fall work the best for us, the same places," he said. "Nothing like Chicago for me, or Dover, Charlotte, Martinsville. Those are great tracks."

BIG RED NOSE: Hometown favorite Denny Hamlin was feeling a bit embarrassed after causing Truex to crash, and costing him the win.

Hamlin said he and Truex "drove in really, really deep. When I got on the brakes, the splitter slammed down on the ground and shot me up the track into him. We weren't racing for the win or anything. I definitely didn't want to get into him. He's a great teammate.

"They tell me I'm a hero around here. Today I was a clown."

GANASSI DUO: Chip Ganassi Racing got both its drivers in the playoffs when Jamie McMurray took the 16th and final position. That already makes it a great week for the car owner; driver Scott Dixon heads into next week's IndyCar Series finale only three points away from his fifth championship.

UP NEXT: The opening round of the 10-race playoffs Sunday at Chicagoland Speedway. There will be 16 drivers at the start of the playoffs, and the field will be cut by four after the third race of the series.