The second sample from suspended NASCAR driver AJ Allmendinger’s recent drug test will be checked July 24 by Aegis, NASCAR’s drug testing company, according to Allmendinger’s business manager.

Tara Ragan, vice president of Walldinger Racing, said Allmendinger’s so-called “B” sample will be tested at 9 a.m. ET July 24 at the Aegis laboratory in Nashville, Tenn.

Allmendinger was temporarily suspended by NASCAR July 7 after he failed a drug test that was administered the previous week. If the B sample from the same test proves positive, Allmendinger’s suspension would be changed to indefinite, and he would be required to go through a rehabilitation process to return to NASCAR competition.

Allmendinger has missed two Sprint Cup races with his No. 22 Penske Racing team. Sam Hornish Jr. has filled in for those events. There is no Sprint Cup race this weekend. The next race is July 29 at Indianapolis.

Ragan said Allmendinger will have an independent toxicologist on site for the sample testing.

“Along with everyone else, we are looking forward to hearing the results as quickly as possible,” Ragan said. “AJ and all of us at Walldinger Racing have truly appreciated the outpouring of support from our fans, partners and colleagues. It has meant a lot to us during this difficult time. We are also grateful to Mr. Penske (team owner Roger Penske) and his management team for their patience and respect of the process we are going through.”

It is not known how soon the results of the test will become available.

Penske said Sunday that Allmendinger would be reinstated to his ride as soon as possible if the B test is negative. If the test proves positive, Hornish is likely to remain in the No. 22 except on weekends when there is a conflict with his Nationwide Series schedule.

Mike Hembree is NASCAR Editor for SPEED.com and has been covering motorsports for 30 years. He is a six-time winner of the National Motorsports Press Association Writer of the Year Award.