Jeff Gluck

USA TODAY Sports

CONCORD, N.C. – Dale Earnhardt Jr. wants to know why there hasn't been more information about what caused Denny Hamlin to miss Sunday's race at Auto Club Speedway.

Hamlin was taken to a local hospital shortly before the race with what Joe Gibbs Racing said was a sinus infection that affected his vision. But Earnhardt wondered aloud why there has been no official NASCAR statement or further explanation from Hamlin on what happened.

Hamlin has not been officially cleared for this weekend's race at Martinsville Speedway.

Earnhardt said there were questions because he'd never heard of a driver being pulled from the race shortly before the start after not being cleared to race by NASCAR.

"I'm worried the perception is bad for NASCAR and the perception is bad for Denny," Earnhardt said Tuesday. "… If Denny didn't race because his vision is blurred and he had a sinus infection, NASCAR should put out a release and say, 'This is the timeline of the events and this is why we made this choice and this is the protocol for going forward.'

"That answers everybody's questions. Don't you have questions? I have questions. We shouldn't have questions. We should all feel pretty comfortable with what happened."

Hamlin tweeted at 6:37 p.m., after Lynda Petty's death was announced: "With due respect to the Petty family i will send out a update tomorrow. Please keep their family in your thoughts tonight."

NASCAR spokesman Kerry Tharp told USA TODAY Sports: "Information regarding Denny Hamlin's health and medical condition should come from Denny and/or Joe Gibbs Racing. As is our policy, Denny will be allowed to return to on track competition after NASCAR receives notification that he has been medically cleared by his physicians to race."

Earnhardt, who missed two races in 2012 after suffering a second concussion in six weeks -- the first of which he hid from doctors until a crash at Talladega Superspeedway caused him further issues, said he wants NASCAR to "look great." For the health of the sport, he said, there should be more transparency about what led to Hamlin's sudden absence. Drivers, like fans, haven't been given many details about Sunday's timeline.

While pre-race ceremonies were taking place, a hastily called news conference informed reporters Hamlin would be replaced by Sam Hornish Jr. due to illness.

"I think he can still drive, but he brought it up and was concerned about it and wanted to make sure it was taken care of," JGR president J.D. Gibbs said Sunday in announcing the absence. "The doctors said, 'Hey, you have to do this right away.' Hopefully it's nothing, but you have to get checked out."

Earnhardt said a statement would clear Hamlin "of any wrongdoing or pressure or rumors."

"If Denny did everything right, that's good to know," he said. "Why NASCAR did the things they did and the timeline, it would be good to know those things because the drivers are all curious and the fans are curious.

"Information is moving around and you're (hearing) conversations with your friends. It just doesn't need to be going on. We should all know what happened and know why it happened and be done with it and not have to worry about it."

Hamlin is expected to see doctors in Charlotte this week. He cannot race until he is cleared by a NASCAR-approved doctor.

If he does not qualify Friday at Martinsville or race on Sunday, he would need another medical exemption from NASCAR in order to remain eligible for the Chase for the Sprint Cup.