Denny Hamlin was held overnight for observation at the University of Alabama-Birmingham Medical Center after a violent crash during Sunday's race.
The right-front tire of Hamlin’s No. 11 Toyota exploded while he was leading on Lap 99 and the car took a hard turn into the outside wall, where it eventually came to rest.
NASCAR officials said Hamlin was awake and alert before he was taken to the hospital. The driver appeared to need assistance getting out of the car after the wreck. Hamlin, 27, is in his third full season in Cup with Joe Gibbs Racing. He was 10th in series points entering Sunday's race.
"He's got a little headache so they're just going to watch him. It was a scary deal, but it's at least nice that he's alert and with it," JGR President J.D. Gibbs said.
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Crew chief Mike Ford said he was unsure what happened to the tire, and did not have a chance to speak to Hamlin.
"But it happened so fast, I doubt he even knows," Ford told The Associated Press.
Hamlin's tire failure was the fourth one in the race and fifth of the weekend. Earlier, Brian Vickers' tire exploded as he was racing for the lead and it triggered an eight-car accident.
"I felt a bomb explode in my right-front tire," Vickers said. "I just went down into the tri-oval and it didn't cut or go flat - it exploded. I saw the right-front fender going through the air before the front of the car even dropped. It was the same thing that happened to (Dale Earnhardt Jr.) in practice.
Earnhardt Jr. had a tire failure during a Friday practice session that triggered a multicar accident.
Ford said on the run before Hamlin's tire failure, the right-rear tire had several cuts in it when the crew removed it during a pit stop. Hamlin attributed the cuts to debris on the race track, so Ford said it was unclear if the later failure was caused by Hamlin running over something or a deficiency in the Goodyear product.
Rick Heinrich, product manager for Goodyear, said the tires used Sunday are the same that were used without incident in the spring event at Talladega. He said David Reutimann's earlier tire failure had "100 percent evidence of a puncture" and Goodyear will have to analyze the other issues at its Akron, Ohio, plant.
"There's a tremendous amount of car contact out there and that loosens things up and drops things on the track," Heinrich said. "There's been accidents. Can't say for sure in every case what happened, but we'll continue to look at it.
Goodyear, meanwhile, is returning to Indianapolis Motor Speedway next week for a two-day tire test to determine why its rubber failed to hold up during the July race. Cars could run about 10 laps without risk of tire failure, and NASCAR called mandatory cautions that forced teams to change the tires and not push them beyond the limit.