From street punk in the projects to world heavyweight champion, Mike Tyson's life has revolved around violence.

That is why it was bizarre to see Tyson's boxing career come to an end so peacefully, as he sat quietly on a stool in his corner while journeyman Kevin McBride paraded around the ring.

Tyson, 38, disgraced himself with his performance on Saturday at the MCI Center but he appeared unmoved. He just sat there, towel draped over his shoulder. No scowls, no emotion.

"When he sat on that stool, he exhaled," said Rock Newman, former manager for champion Riddick Bowe. "The weight of the world was lifted off his shoulders.

"I'd be surprised if he ever leaves that serenity. He'd have to live up to those expectations again."

Tyson retired immediately after the McBride debacle. Boxing writer Bert Sugar said the unheralded Irishman had little to do with Tyson quitting after the sixth round.

"Mike Tyson was beaten by Mike Tyson," said Sugar, recently inducted into the International Boxing Hall of Fame. "There's nothing left inside. He's a classic 'Would have, could have, should have'."

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Michael Gerard Tyson has been trying to live up to lofty expectations ever since he put on a pair of boxing gloves as a youth in the Brooklyn, New York, slum of Brownsville.

Famed trainer Cus D'Amato saw a troubled boy -- arrested at age 12 for purse snatching -- in a reform school and became a father figure to him. He figured boxing would keep Tyson's life from spiralling out of control.

POWERFUL PUNCH

D'Amato, who had managed Floyd Patterson to the top decades earlier, died before Tyson's ascent through the ranks. Tyson lost his confidant, his stability and his way.

He did not, however, lose his powerful punch. Though D'Amato died shortly after his protege's 1985 professional debut, Tyson won his first 19 fights by knockout.

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None of those lasted more than six rounds. In fact, 12 of those fights ended in the first round.

By the age of 20, Tyson became the youngest champion of all time when he pummelled Trevor Berbick during a second-round knockout.

Tyson won his first 37 fights but his out-of-the-ring life had become golden fodder for the tabloids. Street brawls, drug use and accusations of wife-beating provided just some of the headlines.

"The demons," said Sugar. "He couldn't escape the demons. He'd become a lounge act. He was the Michael Jackson of boxing."

The pinnacle of his career occurred in 1988 when he knocked out Michael Spinks in 91 seconds. He was aptly dubbed "The Baddest Man on the Planet".

Tyson now says his career ended in 1990 when he lost to 42-1 underdog Buster Douglas. Two years later in 1992 he was convicted of raping a beauty pageant contestant and sent to prison for three years.

Although he ultimately regained the WBC and WBA heavyweight titles, the demons still lurked. He lost to Evander Holyfield and, during their rematch in 1997, he bit Holyfield's ear and was disqualified.

EMPTY WALLET

Tyson fought for the title once more but was whipped soundly by Lennox Lewis in 2002. Since then, saddled by broken marriages, an empty wallet and a lot of indifference, Tyson has fought a bunch of no-names in an effort to resurrect a boxing career on life-support.

What can he do now? He wants to become a missionary outside of the United States because he feels "stigmatised" as a street thug.

Tyson (50-6, with 44 knockouts) does not appear to be the same person who bit Lewis in the thigh during a scuffle at a news conference and told him he wanted to "eat his children".

He seems different from the man who beat up two people in Maryland after his car was hit. He is quieter. During the pre-fight hoopla against McBride journalists heard few of the usual fiery Tyson sound bites.

Tyson was philosophical, introspective and, at times, charming. He talked about his love for raising pigeons. The profane womaniser appears to be gone. But with Mike Tyson you never know.

"He's an international icon," said Newman. "I talked to a high-powered media executive who believes he is marketable on the lecture circuit."

While boxers often stay in the ring too long -- Muhammad Ali, Sugar Ray Leonard and Joe Louis come to mind -- Tyson's epilogue has lasted 15 years.

Sugar is writing a book and lists Tyson as the 100th best boxer of all time. "He should have been much, much higher," he said. "Sad."

He believes Tyson, who remains deeply in debt despite earning hundreds of millions of dollars in the ring, could fight again in Europe, where he is immensely popular.

"He'd draw eyeballs for all the wrong reasons," Sugar said. "But then, he's been doing that for quite a while now."