LAS VEGAS -- It wasn't a bite. It wasn't a broken arm. It wasn't a felony conviction.

This time it was a late punch that led to another disappointing conclusion to a Mike Tyson fight. Tyson knocked Orlin Norris flat on his back after the bell sounded to end the first round Saturday night at the MGM Grand Garden.

The bout was ruled a no contest, and the result leads many, including Tyson himself, to wonder about his future.

"I'm just tired," Tyson said. "I don't even want to fight no more. I just want to go home. I'm really tired of everybody and everything.

"I'm telling the truth. I really don't want to be caught up in the (B.S.), the politics and stuff. They have me under an agreement, but I don't want to do it anymore."

There are many out there who would be happy to see Iron Mike fulfill those words because they are just as tired of him and his antics.

Tyson still has two fights remaining on his MGM contract, but the hotel-casino certainly must question a renewal at this point. Showtime also needs to question its future dealings with Tyson. If he does choose to prolong his career -- there still are big-money fights out there against the likes of Evander Holyfield, Lennox Lewis, George Foreman -- he might discover fighting abroad is the only way to find interested people.

Promoter America Presents can't be too pleased either. Dan Goossen's group has had Tyson for two less-than-stellar fights that were separated by a jail sentence.

"I think it's almost destined for Mike Tyson that whenever he fights, something extraordinary always happens," said Vitali Klitschko, one of the many heavyweights in attendance who hopes to get a shot at Tyson. Another candidate, Shannon Briggs, also was there.

Tyson and Norris were fighting inside when the bell clanged five times, customary when boxers are close together, just in case one doesn't hear it and happens to uncoil a punch. Tyson's short left uppercut came a second later, prompting referee Richard Steele to deduct two points.

Norris slowly got up, walked back to his corner and sat on his stool, but that's where he stayed when the second round started. Replays confirmed Norris' claim that he twisted his right knee as he crumpled to the canvas. He said he couldn't continue.

In a scene that seems to be required for a Tyson fight, Las Vegas Metro Police and security officers swarmed the ring as 12,081 fans, who paid as much as $1,000 to witness another Tyson debacle, chanted obscenities.

Norris exited the ring with the assistance of trainer Abel Sanchez and a policeman. The former cruiserweight champ left the arena on a stretcher. He was taken to Valley Hospital, where he was to undergo an MRI.

The Nevada State Athletic Commission is withholding Tyson's $10 million purse pending a Monday hearing "because I'm Mike Tyson," he said. "And they're probably going to take it again."

Tyson was fined $3 million and suspended indefinitely in 1997 for twice biting Holyfield on the ears.

Norris, who first hurt the knee in 1990 against Bert Cooper, was given his $800,000.

"Anyone who's a boxer or anyone who's a competitor of any sort, whether it's sports or business, if you're able to continue, you continue," Tyson said. "Against Buster Douglas, I could have quit any time. But I took my beating like a man."

Another athlete on the scene, one with intimate knowledge of knee injuries, doubted Norris' claim.

"To me, any time a guy can get up and walk to his corner and then walk out of the ring, the severity of his injury has to be questioned," Atlanta Falcons running back Jamal Anderson said. Anderson, whose father is Tyson's chief of security, is out for the rest of the season after undergoing surgery on his knee.

Ringside physician Dr. Flip Homansky, however, noted, "it takes time for swelling to occur. The pain and the immobilization comes afterward. It doesn't happen all of a sudden."

Goossen also chided Norris, but probably only to protect his investment in Tyson and the undisclosed number of fights they have remaining.

But the issue at stake here isn't if Norris could have continued. It's that Tyson screwed up again. Aside from chewing on Holyfield, Tyson tried to break Frans Botha's arm during a clinch and told the Los Angeles Times recently he would bite again if provoked.

Now he punches after the bell and blames his opponent.

And let's not forget his problems outside the ring: the rape conviction, the return to prison for assaulting two motorists after a fender-bender, the children born out of wedlock to several mothers, the late-night cavorting at a Las Vegas strip club in the days leading up to his fight with Norris (even though he routinely complains his life in the spotlight is ruining his marriage).

We could go on, but we won't.

And neither should Tyson. If he wants to give up boxing, he shouldn't let us hold him back.

Maybe Tyson wants to bow out because his sport and his society are running out of ways to kick him out.