CHARLOTTE, N.C. -- The undisclosed illness that has sidelined Daytona 500 champion Trevor Bayne for more than a month will keep him out of this weekend's Nationwide and Sprint Cup Series races at Charlotte Motor Speedway.
Bayne is scheduled to return in the Nationwide Series, where he drives the No. 16 for Roush Fenway Racing, next weekend at Chicagoland Speedway. He is scheduled to return to his limited schedule for the Wood Brothers at the June 18 race in Michigan.
Bayne appeared set to return for last weekend's All-Star race for the Wood Brothers in the No. 21 he drove to victory at Daytona in February. But after testing at Rockingham Speedway it was determined he physically wasn't ready after the lengthy period of non-activity.
Ricky Stenhouse Jr. will fill in for Bayne in the No. 21 in Sunday's Coca-Cola 600. Stenhouse is fresh off a victory in the Nationwide Series at Iowa. Matt Kenseth will replace Bayne in the Nationwide Series.
"By all standards, Trevor had a great week," Roush Fenway Racing president Steve Newmark said. "His symptoms have completely subsided. He tested at Virginia International Raceway on Tuesday and had one of the fastest Nationwide Series cars on the track."
Newmark said the organization has consulted with the Mayo Clinic and NASCAR's medical staff about Bayne's timetable to return and gotten approval.
"Although Trevor would have preferred to compete in all 900 miles this weekend, he respects and understands our decision and will shift his considerable focus to his return at Chicagoland," Newmark said.
Bayne has been having symptoms of blurred vision, pain in his left shoulder and elbow, fatigue and periods of feeling nauseous since early last month.
The symptoms were originally linked to an apparent insect bite received the Sunday after the Martinsville Sprint Cup race, but there has been no definitive diagnosis even after Bayne spent several weeks undergoing tests in the Mayo Clinic.
"They still are a little challenged to understand why he has the problem he has," team owner Jack Roush said a few weeks ago. "It may be some medical condition that is not too bad subject to medicine and treatment.
"The only thing they know for sure is he had a bug bite, that he had a very strong reaction to it. It affected his arm and shoulder. The appearance of it is it gave him some blurred vision. It is unknown what the rigor of all the temperature and stress and strain and driver has in the seat," he said.
David Newton covers NASCAR for ESPN.com. He can be reached at email@example.com.