AJ Allemendinger has been suspended for testing positive for a banned substance, reports SB Nation's Jeff Gluck, and will not race in Saturday's Coke Zero 400. His "A" sample tested positive, and according to NASCAR has the right to request testing of his "B" sample within 72 hours.
The test was administered during early June's Kentucy race weekend, where Allmendinger finished in ninth place in the Sprint Cut race. NASCAR did not release any further information about the test, including for what substance Allmendger tested positive. Penske Racing will tap Sam Hornish Jr. to replace Allmendinger in the driver's seat of the No. 22 Shell. They released a statement on the suspension: "NASCAR has a strict drug testing program that Penske Racing fully supports. Penske Racing will work with NASCAR through this process and its next steps."
Allmendinger has had trouble with substance abuse before, having been arrested for drunk driving in the fall of 2009.