updated 5:35 p.m. ET June 14, 2005

WASHINGTON - Mike Tyson was sprawled on the canvas, his head stuck oddly between the first and second ropes. Kevin McBride had shoved him down and now he sat there, trying to contemplate whether to get up.

The round was over, and so was Tyson’s career. Nineteen years after he became the youngest man to win the heavyweight title, he was reduced to this.

An Irish heavyweight of little repute was bullying him around. He wasn’t the baddest man on the planet anymore, not the baddest man in Washington, not even the baddest man in the ring.

He was an aging heavyweight who looked older by the minute Saturday night, finally coming to grips with the fact that this was the way it was going to end. It was all Tyson could do to look at referee Joe Cortez, pull himself to his feet and trudge wearily to his corner.

FREE VIDEO 'Over since 1990' June 13: Mike Tyson talks about the defeat Saturday, his massive debts and his future. NBC Sports

Tyson sat on his stool and told Cortez he had enough. Enough for this fight, enough for a tortured career that began with greatness only to spiral out of control and finally end in desperation and sadness.

He said he would fight no more. The sport that allowed him to earn more than $300 million had passed him by, and it was time for Tyson to admit as much.

“This is it,” Tyson said. “It’s finished.”

For those counting, the once meteoric career ended 20 years and 56 fights after it began, with a March 6, 1985, first-round knockout of Hector Mercedes in Albany, N.Y. In those early days Tyson was spectacular, fearsome and unlike anything boxing had ever seen.

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The image of Tyson in his prime was indelible in the minds of boxing fans around the world. For four years he reigned supreme, seemingly unbeatable, knocking out fighters with vicious intensity and making them frightened even to get into the ring.

“How dare they challenge me with their primitive skills,” he once said.

For two decades, fans thought he was the same fighter. Tyson knew better.

The Tyson who fought his last fight at the MCI Center bore a physical resemblance to the Tyson of old. But that was it.

He was just a shell of that fighter, much as he had been since losing to Buster Douglas in what was one of boxing’s greatest upsets in 1990. Tyson hadn’t beaten anyone of significance since stopping Razor Ruddock the next year, yet fans bought tickets to his fights thinking they would see the young lion who thought he would never lose.

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