Daytona 500 winner Trevor Bayne finally returns to active duty this weekend and will be competing in the STP 300 night time race at Chicagoland Speedway on Saturday evening.

Bayne has been sidelined from racing since early April after suffering from a mystery medical condition causing numbness, swelling and blurred vision that saw him twice hospitalised, once for a week at a specialist clinic in Minnesota.

As well as missing six straight Nationwide races, the condition also caused Bayne to miss out on the opportunity of his first-ever All-Star Race appearance.

Bayne will be back with his Roush Fenway team mates Carl Edwards and Ricky Stenhouse Jr. - who has been filling in for Bayne last week, taking over the #16 Wood Brothers Sprint Cup car Bayne would normally have been driving in last-weekend's Coca-Cola 600 had he been well enough. Despite some brushes with the wall, Stenhouse Jr. finished on the lead lap in 11th place on what was his Cup debut. It's just as well that Bayne and Stenhouse are firm friends or else the Daytona 500 winner might be feeling a little insecure right about now.

"I missed you guys!" Bayne beamed at the NASCAR press pack at Charlotte Motor Speedway last weekend with apparently complete sincerity.

"Watching races on TV is not as fun as being in the driver's seat," Bayne told them. "It makes it tougher when your team is running as good as these guys have, too, to know that you could have had a shot at winning these races. The good thing is I get to look forward to that in Chicago."

It seemed clear that Bayne had considered himself good to go again for last week's endurance events in both Cup and Nationwide, and had been rather irked by being replaced by Stenhouse in last week's Cup race and by Matt Kenseth (the eventual winner) in the Nationwide event. "I took last weekend off as a precaution and this week they made me take off as a precaution," he said. "Chicago would definitely be over the top as far as being cautious on what could spark anything.

"I am trying to listen to them, even though I am 20 and stubborn and want to be in a racecar every weekend," he continued. "I would be riding around with an eye patch if they would let me. It's all good. I think we have waited long enough."

Bayne told reporters that "Everything is pretty much 100 percent back to normal and that is pretty exciting," insisting that he had been back to normal "for over a week now,' adding that "missing the All-Star Race kind of crushed me."

Steve Newmark, president of Roush Fenway Racing, confirmed that there was still no news on the underlying cause of Bayne's illness from the doctors at the Mayo Clinic. "Even though there is no official diagnosis and they can't tell us the root cause, they've run all the tests and done everything possible they can do to him and they have declared him fit to get back on the race track."

Bayne described what he had been through over the past six weeks: "I went to bed on a Monday night feeling great and woke up Tuesday and I was seeing two of stuff. And that wasn't cool," he said. "I went to the hospital and had the best doctors in the world at the Mayo Clinic checking me out, and they don't know," he added, describing how "at one point, I had like 16 needles in my body at once - and shock pads and stuff that I didn't even know existed!"

Bayne received treatment for possible conditions related to an insect bite and was checked for conditions such as Lyme Disease, but nothing was conclusive. In the meantime, the symtoms simply cleared up under all the medication.

"There are a lot of highs and lows in this sport," said Michael McDowell, Bayne's close friend and fellow NASCAR driver. "Unfortunately, he's had to experience the extremes in a three-month window," referring both to Bayne's shock Daytona 500 win in February and the recent bout of medical uncertainty.

But Bayne himself has come out of this with his youthful enthusiasm and optimism undimmed.

"I am thankful to be able to get back into a racecar, and I am going to savor this moment forever," he said. "We as racecar drivers are so blessed to be doing this for a living, and I think we take that for granted sometimes. I am ready to get back to work."