Andre Agassi’s upcoming autobiography contains an admission that he used crystal meth in 1997 and lied to tennis authorities when he failed a drug test — a result that was thrown out after he said he “unwittingly” took the substance.

According to an excerpt of the autobiography published Wednesday in The Times, 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 said the ATP reviewed the case, accepted his explanation and threw it out.

ATP spokesman Nicola Arzani said Wednesday he would not comment “at the moment,” and the International Tennis Federation’s Emily Bevan referred all questions to the ATP.

Agassi retired in 2006. Excerpts from his autobiography, which comes out November 9, are being published this week in the London newspaper, as well as Sports Illustrated and People magazines.

According to the Times of London Web site, Agassi writes in his book that “Slim” was the person who introduced him to crystal meth, dumping a small pile of powder on the coffee table.

“I snort some. I ease back on the couch and consider the Rubicon I’ve just crossed,” Agassi writes. “There is a moment of regret, followed by vast sadness. Then comes a tidal wave of euphoria that sweeps away every negative thought in my head. I’ve never felt so alive, so hopeful — and I’ve never felt such energy.

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