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The end came with the shocking suddenness of many Mike Tyson (search) fights. First, the flurry of devastating punches, then a fighter falling bleeding to the canvas.

Even more shocking this time was that fighter was Tyson himself.

A comeback born out of financial desperation didn't go past the fourth round Friday night when an unheralded British heavyweight by the name of Danny Williams (search) knocked Tyson out with a savagery that may have once and for all exposed Tyson as a shot fighter.

At age 38, Tyson ran out of energy after trying to put Williams down for the first three rounds and was driven to the canvas with a final right hand that may have signaled the end of his hopes to become a serious heavyweight contender again.

"Once I hurt him I just let go," said Williams, who had fought only once in the United States. "I just kept punching and punching."

Beaten and battered, Tyson laid helplessly along the ropes, blood flowing down his face. The former baddest man on the planet stared ahead with a look of resignation on his face as his latest comeback — and perhaps his tumultuous career — collapsed along with him.

Now, after 19 years as a pro, his record stands at 50-5-2. This loss was Tyson's first in a non-title fight.

In his corner, Tyson apologized to his trainer. Across the ring, Williams celebrated and then proposed to his girlfriend — who accepted.

And somewhere, lawyers began trying to figure out how Tyson could pay off $38 million in debt when his asking price will surely plunge after such a devastating defeat. He earned about $8 million to fight Williams but will probably see all but $2 million go to his creditors.

"People forget this isn't a peak Mike Tyson," said Williams, who now is 32-3 with 27 knockouts. "I thought I could win."

Williams ended a wild slugfest with a flurry of punches that sent Tyson sprawling into the ropes late in the fourth round. With blood streaming down his face, Tyson appeared to contemplate the end, then made a halfhearted effort to get up before the fight was called at 2:51 of the fourth round.

"I'm sorry. I'm disappointed," Tyson told trainer Freddie Roach.

"You don't have to be sorry with me," Roach replied.

Tyson's handlers said later he injured his knee late in the first round. He was taken to a hospital to get stitches for a cut near the corner of his right eye and a precautionary CT scan.

"I felt like I had him," Williams said. "I just remember [Evander] Holyfield fighting him that Holyfield kept coming with shot after shot."

The fight was a free-for-all from the opening bell before an excited crowd at a nearly full Freedom Hall. Tyson landed some huge left hooks early, only to take punishment himself when Williams got over his initial stage fright and began brawling.

Fighting in Muhammad Ali's (search) hometown before a crowd that cheered his every move, Tyson tried with every punch to score the kind of spectacular knockout that would make him a heavyweight contender once again.

But Williams wouldn't go down, weathered the storm, and then came back to dish out more punishment.

"He was a strong guy with a lot of heart," Roach said of Williams. "He showed us things that we didn't see in films. He seized the opportunity of a lifetime."

Tyson, who left without talking, won the first three rounds, but Williams was landing well to the head. When he began throwing punch after punch with Tyson near a neutral corner, Tyson couldn't answer back.

It was Tyson's first fight in 17 months, and only his second since taking a beating from former heavyweight champion Lennox Lewis two years ago. But Lewis was a legitimate world champion, while the 31-year-old Williams' biggest claim to fame was winning the British heavyweight title.

Tyson was desperately trying to resurrect a career that made him more than $300 million which he squandered. But the loss to a 9-1 underdog perhaps signals the end of an era in the heavyweight division

"We didn't think he could stand up to the pressure of the first few rounds," Roach said. "Danny Williams surprised a lot of us."

The crowd of 17,253 came to see a knockout by Tyson, and when Tyson rocked Williams with a big uppercut and some left hooks in the first two rounds it looked like they would get what they came for.

But Tyson was cut in the third round, and Williams showed he was going to be the bully in this fight. He hit Tyson on the break, losing a point, then hit him low, and the referee took another point.

The bully was being bullied, and Tyson couldn't stand up to it.

"Every single round that went by, his punching power seemed to grow less," Williams said. "So I knew I was going to take him out."