CHARLOTTE, N.C. (MCT) — NASCAR’s most popular driver, Dale Earnhardt Jr., will sit out at least the next two Sprint Cup Series races after suffering a second concussion within six weeks.

Earnhardt’s neurosurgeon, Dr. Jerry Petty, notified him Wednesday he would not be cleared to race in Saturday night’s Bank of America 500 at Charlotte Motor Speedway.

“I trust his opinion. That’s why I went to see him. He’s been a good friend of mine for a long time and has helped me through a lot of injuries before,” Earnhardt said of Dr. Petty.