Updated

Kyle Busch had a dominant day and scored Joe Gibbs Racing’s first Sprint Cup victory Sunday at Auto Club Speedway as new rivals Denny Hamlin and Joey Logano crashed while racing for the lead on the last lap.

Busch had the car to beat all day but needed conflict between Logano and Hamlin to win the Auto Club 400, the fifth race of the season.

Hamlin and Logano, whose feud accelerated with issues at Bristol Motor Speedway, raced side by side for the lead on the last two laps. They made contact on the white-flag lap as Busch slipped by on the outside to take the lead and, a few seconds later, the win.

Logano hit the outside wall, while Hamlin’s car slammed hard head-on into the inside wall. He was removed from the crash scene in an ambulance. Although Hamlin was reported to be awake and alert in the infield media center, he was transported by helicopter to an area hospital for evaluation.

After the race, Tony Stewart charged Logano, angered by Logano’s blocking maneuver on the final restart. “I’m going to bust his ass,” said Stewart, still mad 15 minutes after the race. Logano admitted that he blocked “to protect the spot.”

RESULTS: Auto Club 400

While Logano and Hamlin wrestled for the lead with the checkered flag in sight, Busch suddenly appeared on the outside and slipped by smoothly to win the race.

“They forgot about me,” Busch said. “I knew they were going to. I was hoping I could get by before they wrecked. I put my foot to it and drove around the outside of them, maybe as they were crashing. If they had been single-file and not racing, it would have gone down as it was.”

Busch led Logano with 15 laps to go when Clint Bowyer, in 10th, blew an engine to put the field under caution. That prompted one of a series of wild restarts as the leaders spread across the wide track trying to grab positions on the first green-flag lap.

Busch was able to push around the rest of the field for much of the day. He led 48 of the first 89 laps and 75 of the first 120.

In the second half of the race, he wrestled battery issues but switched to a backup and returned to contend at the front.

Busch had a five-second lead over Kevin Harvick with 30 laps to go when Marcos Ambrose blew a left-rear tire to bring out the afternoon’s sixth caution. It was the second time Ambrose had lost a left-rear tire.

Several contenders faced an early issue as Timmy Hill’s car split an oil line on lap 37, spreading oil on the track surface. Several cars slipped in the oil and whacked the outside wall. Drivers who left the accident area with minor damage included Kasey Kahne, Mark Martin, Kurt Busch, Jeff Gordon, Bowyer and Brad Keselowski.

Dale Earnhardt Jr. raced in the top five at the event’s halfway point and was in third when he pitted under caution with 80 laps to go. Pit-crew problems with the right rear tire cost Junior 20 seconds in the pits, and he fell to 21st place.

But Junior burst through the field over the wild closing laps and finished second in the last-lap mayhem.

That run gave Junior the point lead as Keselowski fell to second, 12 points back.

Kurt Busch finished third.

Mike Hembree is NASCAR Editor for SPEED.com and has been covering motorsports for 31 years. He is a six-time winner of the National Motorsports Press Association Writer of the Year Award.