Kyle Busch reveals why he collapsed Sunday at Charlotte

Kyle Busch had a rough day on the track on Sunday at Charlotte Motor Speedway, and it got worse when the race ended as he collapsed to the ground.

Busch said he felt sick during the last 200 laps of the race, and after the race he said he felt like he had a heatstroke.

"I'm all right," Busch said via Bob Pockrass of ESPN. "I'm better now. ... It just got so hot, that literally, you felt like you were going to puke and just trying to make it to the end of the race and luckily we did.

"And from there, [they were] just trying to get cooled back down and get my body temperature back to normal.

"I felt like I had heatstroke just from being inside the race car for 200 laps with the crush panels knocked out of it," said Busch. "Overall, it was just the hottest I've been in the car. ... I didn't feel sick from the CO or anything like that. I just felt heatstroke."

Related: Kyle Busch gave fans a scare after the race in Charlotte

Busch crashed in the wall during the race, which caused damage to his 18 car. His team went to work to repair the damage, but he continued to have trouble for the remainder of the day.

His crew gave him ice bags during pit stops, and after the race he fell to the ground due to the heat exhaustion.

Busch finished 29th, which obviously isn't an ideal finish for a championship contender, but he had just won back-to-back races. So he has some margin for error in qualifying for the Round of 8, though he and his team will certainly want a better performance on Sunday at Talladega.

Martin Truex Jr. won Sunday's race at Charlotte, which was his sixth victory of the season.

(h/t ESPN)