Bjorn Borg, of Sweden, competes in the French Open at Roland Garros Stadium in June 1976.

Borg falls to his knees on Centre Court at Wimbledon in July 1980, after beating John McEnroe to win his fifth successive title.

Bjorn Borg shakes hands with John McEnroe (right) after losing the US Open final 4-6, 6-2, 6-4, 6-3 at the National Tennis Center in New York in September 1981. It was a rematch of the previous year's final, which Borg also lost. He quit tennis in the wake of the defeat.

Borg lifts the Wimbledon trophy in July 1980 after winning his fifth consecutive title at the All-England Club.

Bjorn Borg starts his new memoir, "Heartbeats", with a story about being rushed to a Dutch hospital in the 1990s after overdosing on "alcohol, drugs, pills — my preferred ways of self-medication", and the Swedish tennis great closes it by revealing that he was diagnosed with prostate cancer.

"It's good," Borg, 69, said in a recent video interview with reporters from his home in Stockholm, "to have a good beginning and a good ending."

In between, the 292-page book, which will be released in the United States by Diversion Books on Sept 23, contains revelations about his love life, various adventures and regrets, and the 11-time Grand Slam champion's detailed recollections of particular matches.

Borg quit tennis at age 25 because he stopped caring when he lost.

Famously private, Borg kept a lot to himself during his days on the Tour — and remained so since he surprisingly retired in his 20s.

He brings readers back to when, having lost the 1981 Wimbledon and US Open finals to rival John McEnroe, Borg realized he was done.

"All I could think was how miserable my life had become," he writes.

He was 25 and, while he would briefly return to tennis, he never competed at another Grand Slam event.

After the 1981 US Open final, a tournament he never won, Borg grabbed some beers and sat in the pool at a house on Long Island, where friends planned a party to celebrate a victory.

"I was not upset or sad when I lost the final. And that's not me as a person. I hate to lose," he told the reporters.

"My head was spinning," he said, "and I knew I was going to step away from tennis."

Borg wasn't always calm on a tennis court.

Borg writes about his childhood and his relationships with his parents (and, later, his children).

He writes about earning the nickname "Ice-Borg" for his calmness on court — often contrasted by fans to the more fiery McEnroe and Jimmy Connors. And Borg writes that did not come about "organically", but rather via "the bitter experiences" of a 12-year-old kid.

"I behaved so badly on the tennis court. I was swearing, cheating, behaving in the worst way you can imagine," he recalled in the video interview.

He said his hometown tennis club banned him for six months and, when he returned, "I did not open my mouth on the tennis court, because I was scared to get suspended again."

"Boiling inside? Yes," Borg said. "I had to control my feelings. You cannot do that in one week. It took years to figure out how I should behave on the court."

Borg also discusses cocaine and two overdoses that landed him in the hospital.

He writes about panic attacks and his drug use, which he says started in 1982.

"The first time I tried cocaine," he says in the book, "I got the same kind of rush I used to get from playing tennis."

He also writes about "the worst shame of all", which he says came when he looked up from a hospital bed in Holland to see his father. Borg also clarifies that an earlier overdose, in 1989 in Italy, was accidental, not a suicide attempt.

"Stupid decision to be involved with this kind of thing. It really destroys you," he said about his dabbling with drugs. "I was happy to get away from tennis, to get away from that life. But, I had no plan what to do. I had no people behind me to guide me in the right direction."

There were other people, though. Some surprising names appear in the memoir, in which, Borg paints the picture of a remarkable life.

He recalls a water-skiing injury to his shoulder before the 1977 US Open and death threats during the 1981 tournament. He tells of getting paid in cash — and getting robbed at gunpoint; a woman claiming he was the father of her son and a coin-throwing incident by spectators in Rome that led him to never return.

This is not the typical sports autobiography: He references messaging Yasser Arafat and, five pages later, the phrase: "Andy Warhol was someone easy to like" appears. There are name-drops of Donald Trump, Nelson Mandela, Tina Turner and "my old friend Hugh Hefner", among many, many others.

"People will be very surprised what really happened," Borg said. "For me to come out (after) all these years, all I went through — I went through some difficult times — (it's) a relief for me to do this book. I feel so much better. There are no secrets anymore."