American tennis legend Andre Agassi has admitted using crystal methamphetamine a year before he won the French Open in 1998, and that he lied to the sport’s governing bodies in the same period about a positive drugs test to avoid a ban.

The 39-year-old, who is only one of six men in history to have completed a career grand slam of winning titles at all four majors, confessed in his autobiography that he took the highly addictive narcotic in 1997 while suffering poor form and to quell worries about his upcoming marriage to actress Brooke Shields.

The eight-time grand slam champion revealed in his book how he felt when he first took the substance — possession of which carries a maximum five-year jail sentence in the United States.

“Slim [Agassi's assistant] 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 recounted in an excerpt of his book that has been serialized by British newspaper The Times.

Following his use of crystal meth, the former world number one pulled out of the French Open and admitted he did not practice for Wimbledon a month later.

Later in the year an Association of Tennis Professionals (ATP) doctor confirmed to Agassi — who is currently married to former number one women’s tennis player Steffi Graf — that his use of recreational drugs had shown up in a positive dope test and that he faced a three-month suspension.

The tennis great revealed how he lied in a bid to retain his reputation: “My name, my career, everything is now on the line. Whatever I’ve achieved, whatever I’ve worked for, might soon mean nothing. Days later I sit in a hard-backed chair, a legal pad in my lap, and write a letter to the ATP.

“It’s filled with lies interwoven with bits of truth. 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. I feel ashamed, of course. I promise myself that this lie is the end of it,” Agassi added.

Following the letter from Agassi the ATP dropped the case, allowing the American to regain a form that would see him go on to win the French Open in 1998 and the U.S. Open in 1999 before retiring in 2006.

The ATP have yet to comment following the revelations.