Daytona 500 winner Trevor Bayne will sit out for a fifth consecutive week as he continues to recover from fatigue and blurred vision caused by an unexplained illness.

Roush Fenway Racing termed the decision “precautionary” and plans for Bayne to return next week for the Nationwide Series race at Chicagoland Speedway.

Bayne was scheduled to drive in the Top Gear 300 Nationwide Series event on Saturday and the Coca-Cola 600 Sprint Cup event on Sunday at Charlotte Motor Speedway.

He has tested the last two weeks, but Roush Fenway announced Wednesday that Bayne would not compete in what would have been 900 miles in two days.

Instead, he will resume his Nationwide driving duties next week at Chicagoland and return to the Wood Brothers Racing car for its next scheduled event June 18 at Michigan.

“By all standards Trevor had a great week,” Roush Fenway Racing President Steve Newmark said in a statement. “His symptoms have completely subsided. He tested at Virginia International Raceway on Tuesday, had one of the fastest Nationwide Series cars on the race track and his team was extremely pleased with his progress.

“As a result, we plan to have him back in competition next week in Chicago.”

While Bayne is sitting out again this weekend, Ricky Stenhouse Jr. will make his first Sprint Cup start by replacing Bayne in the Wood Brothers Racing car for the Coca-Cola 600. Stenhouse, who earned his first NASCAR victory by winning the Nationwide event at Iowa Speedway last week, will have to qualify on speed.

Matt Kenseth will replace Bayne in the Nationwide car this weekend.

The 20-year-old upset winner of the Daytona 500, Bayne spent about 10 days in the Mayo Clinic in Minnesota as doctors tried to determine what caused his illness.

Doctors have termed it an inflammatory condition, and Roush Fenway officials said they have not determined a definitive cause.

Bayne suffered either an insect or spider bite in April and was briefly hospitalized for swelling and numbness. He has said the bite is not believed to have been the cause of his illness.

Bayne has dropped to 14th in the Nationwide Series standings after missing the last four races. The Coca-Cola 600 is the second Cup event he will miss as part of a planned partial-season schedule.

“Of course, Trevor is a competitor and he wanted to be back on the race track this weekend,” Newmark said. “However, we feel it is in his best interest for us to exercise an abundance of caution with this matter and withhold him from racing this weekend, especially considering the length of the races and the fact that Trevor is just starting to get back into his daily routine.”