Agassi admits that he used crystal meth

Andre Agassi's upcoming autobiography contains an admission he used crystal meth in 1997 and failed a drug test — a result thrown out after he lied by saying he "unwittingly" took the substance.

According to an excerpt of the autobiography "Open" published Wednesday in The Times of London, the eight-time Grand Slam champion writes that he sent a letter to the ATP tour to explain the positive test, saying he accidentally drank from a soda spiked with meth by his assistant "Slim."

"Then I come to the central lie of the letter," Agassi writes. "I say that recently I drank accidentally from one of Slim's spiked sodas, unwittingly ingesting his drugs. I ask for understanding and leniency and hastily sign it: Sincerely.

"I feel ashamed, of course. I promise myself that this lie is the end of it."

Agassi, who married tennis star Steffi Graf and has two children, retired in 2006.