Tyson Gay (center) ran in the IAAF Diamond League Grand Prix in May in New York. (John Minchillo / AP)

Tyson Gay, holder of the American 100-meter record, has tested positive for a banned substance and will not run in the world championships next month in Moscow.

Gay did not reveal the substance involved but told the Associated Press that he learned Friday from the U.S. Anti-Doping Agency that a sample from an out-of-competition test May 16 was positive.

“I don’t have a sabotage story. I don’t have any lies,” a tearful Gay told the AP. “I don’t have anything to say to make this seem like it was a mistake or it was on USADA’s hands, someone playing games. I don’t have any of those stories. I basically put my trust in someone and I was let down.”

Gay declined to identify who that person is. “I can’t really say it. Sometimes a human being naturally, generally trusts somebody. That’s what people do.”

Gay, 30, won the 100 and 200 at nationals last month. He plans to have his second, “B” sample tested soon. He had been part of USADA’s “My Victory” campaign, pledging to compete cleanly, and said he has spoken to his family and friends about the positive test.

“They already know it is some type of accident, or some type of — I don’t want to use certain words, to make it seem like an accident, because I know exactly what went on, but I can’t discuss it right now,” he said. “My career and my name have always been better than medals or records or anything like that. I’ve always wanted a clean name with anything. Unfortunately, I have to break this news, that I have a positive ‘A’ sample.”

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