CHARLOTTE, N.C. -- A day after learning Jeremy Mayfield failed a drug test for something other than a performance-enhancer, NASCAR allowed him to drive a race car at Darlington Raceway at speeds up to 173 mph.
A person familiar with the test results told The Associated Press on Thursday that Mayfield's positive test was not for a performance-enhancing drug. The person spoke on condition of anonymity because NASCAR won't reveal what banned substance was found in the random test, which ultimately resulted in Mayfield's indefinite suspension.
NASCAR officials previously announced the drug violation was not alcohol-related, and the administrator of its drug testing program has dismissed Mayfield's explanation that the positive result came from a mix of a prescription with an over-the-counter medicine.
Under the sport's toughened policy, that leaves the possibility that Mayfield tested positive for abuse of a prescription drug, narcotics or controlled substances, such as cocaine, marijuana or methamphetamine.
Ryan Newman called on NASCAR to reveal the substance.
"There should not by a mystery out there," he said before the annual Pit Crew Challenge. "This should be public knowledge. If we're going to do what's good for the sport, which is also what's good for kids that are out there that look up to NASCAR drivers, they should know what not to do.
"That's super important to me. I don't know the whole story for what's happened. Knowing what the penalty is, knowing what caused the situation is extremely important," he said.
Because Mayfield challenged the initial positive finding, as allowed under NASCAR's drug policy, the series did not take disciplinary action until his backup "B" sample also tested positive. That's why Mayfield wasn't barred from participating in two practice sessions and a qualifying session May 8 at Darlington.
"There are limitations as to how quickly the process can be brought to conclusion," said Dr. David Black, the administrator for NASCAR's drug-testing program. "The practical reality is there is going to be a delay. In an ideal world, if the world were perfect and there was a possibility of an instant answer, we'd be able to take immediate action."
NASCAR finds itself in a unique position in its first season under the toughened drug policy. While other major sports leagues must focus on the effects of performance-enhancing drugs on their traditions and records, the abuse of recreational drugs and the altered states they create can present an imminent danger in NASCAR, where 43 cars are on the track at once, racing at high speeds in 3,400-pound cars.
Drivers had mixed feelings as to whether Mayfield should have been allowed on the track while his "B" sample was analyzed. Newman called it "scary," because he wasn't sure what effects the substance might have had on Mayfield. Brian Vickers said he had no issue if NASCAR deemed Mayfield competent to drive.
"If someone tests positive, there ought to be a period of time that allows for a 'B' sample review, and you'd hope that review of time wouldn't keep him off the track," said Jeff Burton, one of NASCAR's most outspoken safety advocates.
"But I think when you test positive, it should be released to add credibility to the program. Although it might ruin someone's career, the credibility of the program is more important. But you've got to be 100 percent without a doubt, with an 'A' and 'B' sample, before you are guilty," he said.
Mayfield was first told on May 5 that he had failed a random drug test and was asked to explain why he might have tested positive, according to an outline of NASCAR's procedures provided by Black, CEO of Aegis Sciences Corp. in Nashville, Tenn., which runs the testing program.
After Aegis investigated Mayfield's explanation and rejected it, Black's office told NASCAR officials on May 7 about the positive test.
On May 8, Mayfield showed up at Darlington, ready to get on the track, and asked for his backup "B" sample to be tested. NASCAR put a rush on the lab order to learn the results before the Southern 500 on May 9.
While they waited, Mayfield took part in two practice sessions with other cars on the track alongside him.
Black would not speculate if allowing Mayfield on the track put Mayfield or the other drivers in danger.
"We didn't collect a sample that day on the individual, so I can't predict without the test result, to know if the person had consumed the drug of concern," Black said.
Mayfield ran 16 laps in the first session, 23 laps in the second with a fast lap of 173.577 mph. Mayfield later ran two qualifying laps alone on the track but failed to qualify for Saturday night's race.
"Certainly we were in contact with Jeremy that day, and there was no physical reason to believe he couldn't perform," NASCAR spokesman Ramsey Poston said. "Dr. Black's team had a rush order to get us the results. They literally worked through the night so we would know the 'B' sample before Saturday night's race."
With 43 cars on the track at once, the abuse of recreational drugs could present a safety issue for NASCAR.
"It's unique in the much greater potential of life-and-death," said Dr. Gary Wadler, who leads the committee that determines the banned substances list for the World Anti-Doping Agency.
Using banned substances can be dangerous to competitors in other sports -- what if in football, the entire offensive line is on steroids and none of the defensive linemen is?
But in auto racing, Wadler said, "it's a different order of magnitude." So he believes NASCAR would be justified to make its rules even stricter than those in other sports.
"Therefore you have to go the extra mile to fully protect the innocent," he said.
This season, NASCAR, which previously only tested when there were reasonable suspicions, ordered preseason testing for all drivers and crew members and added random testing throughout the season. NASCAR provided teams last December with a detailed list of banned substances it would test crew members for this season.
No such banned list exists specifically for drivers because NASCAR reserved the right to test for anything it wants above and beyond the baseline crew member list. To Wadler, that undermines the legitimacy of the program.
NASCAR won't disclose what Mayfield tested positive for, but Black said it was out of respect to the individual's privacy and not because it would violate federal HIPAA laws.
"The reason we don't reveal the substance is because our policy says the misuse or abuse of any substance is a violation," Poston said. "The substance is irrelevant. What's important is that a drug, under a positive test, a drug has been misused or abused."
Several drivers called on NASCAR to provide them with a list of substances they can't take under the testing program.
"If [a driver] doesn't want a list, then they don't care," Newman said.