Daytona Beach, FL (Sports Network) - Suspended driver A.J. Allmendinger will have his "B" sample tested next week, NASCAR said in a release on Tuesday.

Allmendinger was temporarily suspended by NASCAR on July 7 for violating its substance abuse policy. The 30-year-old driver from Penske Racing failed his initial drug test that he took the last weekend in June when the Sprint Cup Series competed at Kentucky Speedway.

NASCAR said it has been informed by the NASCAR Substance Abuse Policy Program Administrator, Dr. David Black of Aegis Sciences Corp., that Allmendinger's second sample will be tested on July 24 at Aegis' headquarters in Nashville, Tenn.

Allmendinger has elected to have a designated independent toxicologist present during the test.

"Along with everyone else, we are looking forward to hearing the results as quickly as possible," Allmendinger's business manager, Tara Ragan, said in a statement. "A.J. 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. (Roger) Penske and his management team for their patience and respect of the process we are going through."

Allmendinger has missed two Sprint Cup races so far -- Daytona and New Hampshire. Sam Hornish Jr. has driven Penske's No. 22 Dodge in place of Allmendinger. Hornish is a full-time competitor in the Nationwide Series.

NASCAR has yet to reveal the substance, but Ragan said in a recent release that Allmendinger "tested positive for a stimulant" and "has no idea why the first test was positive, and he has never knowingly taken any prohibited substance."

If Allmendinger's "B" sample comes back positive, NASCAR will then place him on indefinite suspension, meaning he will have to successfully complete a drug treatment program before he can be reinstated.

NASCAR's premier series is off this coming weekend before it returns to racing on July 29 at Indianapolis Motor Speedway.

The Sports Network