Kurt Busch will miss this weekend's NASCAR Cup Series race at Indianapolis Motor Speedway.
His 23XI Racing team revealed that NASCAR has not medically cleared Busch to return. The 43-year-old sat out last Sunday's event at Pocono Raceway after sustaining concussion-like symptoms from a crash during the previous day's qualifying session.
Ty Gibbs, who finished 16th when replacing Busch last weekend, will once again drive the No. 45 Toyota in place of the 2004 Cup Series champion.
Busch thanked his crew and sponsors for "putting my health first" in a Twitter statement confirming he's not cleared to compete.
"I remain dedicated to focusing on my recovery and getting back on the track and will continue to work closely with NASCAR's medical team and my own team of doctors," Busch wrote.
Per 23XI Racing, NASCAR has granted Busch a medical waiver that keeps him eligible for the Cup Series playoffs. He's currently 17th in the season standings.
The team co-owned by Michael Jordan and Denny Hamlin will again turn to Gibbs, the grandson of former NFL coach and Joe Gibbs Racing founder Joe Gibbs. He wished Busch a speed recovery and said his goal this Sunday is "just to complete the race and learn all we can."
Busch has hinted at retiring from NASCAR after the season, so fans will hope to see him back behind the wheel soon.