LOS ANGELES, California (X17online) - In a new biography, tennis star Andre Agassi admits to having used the powerful drug, crystal methamphetamine, then lied about it to the Association of Tennis Professionals when it was detected during a drug test.

In an excerpt from the book obtained by The Times, he writes about his first encounter with the drug in 1997, when his career was starting to fade and he was having troubles in his marriage to Brooke Shields.

He writes that his assistant, whom he calls "Slim", first introduced him to the drug:

“Slim is stressed too ... He says, You want to get high with me? On what? Gack. What the hell’s gack? Crystal meth. Why do they call it gack? Because that’s the sound you make when you’re high ... Make you feel like Superman, dude.

As if they’re coming out of someone else’s mouth, I hear these words: You know what? F*** it. Yeah. Let’s get high.

Slim dumps a small pile of powder on the coffee table. He cuts it, snorts it. He cuts it again. I snort some. I ease back on the couch and consider the Rubicon I’ve just crossed. 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."

Agassi later details how he lied to the ATP after he failed a drug test to avoid a three-month suspension. He sat down to write the association a letter:

“I say Slim, whom I’ve since fired, is a known drug user, and that he often spikes his sodas with meth — which is true. Then I come to the central lie of the letter. 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."

The ATP eventually threw the case out.