DAYTONA BEACH, Fla. (AP) -- AJ Allmendinger was silent Sunday, a day after NASCAR suspended him for failing a random drug test.

Penske Racing, which gave Allmendinger the biggest break of his career this season, is withholding judgment until NASCAR's system has been completed.

Where that leaves the 30-year-old driver remains to be seen.

There is no second test coming for Allmendinger, who was randomly summoned June 29 in Kentucky to provide a urine sample to NASCAR. Per NASCAR guidelines, the specimen was split in two for an "A'' and a "B'' samples. NASCAR announced 90 minutes before Saturday night's race at Daytona that Allmendinger's "A'' sample had failed the test.

NASCAR didn't reveal what Allmendinger tested positive for, and Allmendinger hasn't commented publicly since the announcement.

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