LAS VEGAS, MAY 31 -- Pinklon Thomas, once so pretty in his pink-trimmed white silks, was in shreds. He had abrasions on his forehead, cuts on his cheek and above his left eye, and a dislocated shoulder. Mike Tyson had done this.

Tyson, 20, no robe, no socks, just a stark pair of black shoes and shorts and two fistfuls of gloves, did all that on his way to a sixth-round technical knockout of his challenger. He did it on his way to retaining his World Boxing Council and World Boxing Association titles Saturday night at the Las Vegas Hilton. He did it messily and destructively, some of it with his inadvertent, bull-like head butts, some of it with elbows gone awry, but most of it with those looping, long distance blows.

"Heavy punches with bad intentions," he called them.

Thomas, a former WBC champion who once was master of the left jab and at 29 was trying to come back after losing his title to Trevor Berbick last March, had promised an aggressive and intelligent fight. Someday, someone will give that to Tyson, whose considerable talent still lacks polish. But in the meantime, it seems likely that Tyson will go on with his mad charges and, if challengers are, like Thomas, without speed, movement and hurtful punches, they will suffer the same fate.

"Right now, Mike's a tough cookie to crack," Thomas said. "Hey, the guy's a good fighter; he's worthy of the position. I take nothing from him."

The chief thing Tyson accomplished Saturday night was to end the doubts that arose from his last bout, a yawning 12-round decision over James (Bonecrusher) Smith that was a hug-and-paw affair and did nothing for his reputation. He intended to remedy that with early rushes at Thomas, and it worked.

"I want them to keep having doubts," Tyson said. "I want everyone to have doubts when they come in the ring with me."

The champion's drive to unify the title will continue when he returns here on Aug. 1 to meet newly crowned International Boxing Federation champion Tony Tucker. Tucker won the vacant title earlier Saturday night with a 10-round technical knockout of No. 2 contender James (Buster) Douglas.

Tucker also has said he will give Tyson an aggressive bout, and so has Tyrell Biggs, another contender who will have his shot sometime. But more and more, opponents are choosing to drape themselves over Tyson's shoulders and hope to avoid the more devastating blows. That is what Smith did, although Thomas took more of a middle road, working away inside and resting in clinches periodically. All it got him was a brief delay before the first knockdown of his career.

He was lucky to avoid it in the very first round, which was murderous. Rounds two through five were a succession of clinches, remarkable only for boos from the crowd and Tyson's demonstration that he learned from the Smith fight how to break free of wrestle-holds.

Finally came the sixth. After more clinching, Tyson broke loose. He stepped back and caught Thomas with a right uppercut that set him reeling backward and jerked his right shoulder out of joint, then followed with a right uppercut to the head. Tyson pressed in with a left hook, and then began dropping blows like small bombs, as many as seven unanswered, spinning Thomas around. Another left hook finally dropped him in Tyson's corner of the ring.

Referee Carlos Padilla began the count, which got to eight before Thomas started to rise. By then Angelo Dundee had rushed into the ring, and Padilla stopped the fight two minutes into the round.

"I was defenseless," Thomas admitted. "There was nothing I could do."

Then came the usual excuses, from Thomas for not fighting more competitively (he had problems with his left glove between the fifth and sixth), and Tyson for not ending it earlier (he felt the hot weather in the third). But if nothing else, Thomas demonstrated in a couple of rounds that Tyson has some vulnerabilities, and much to learn. Tyson's trainer, Kevin Rooney, said so afterward, and so did Tyson.

According to Rooney, Tyson didn't listen to his corner, and he didn't throw enough jabs. Tyson is uncomfortable with clinches, when he has a habit of becoming inactive. Rooney became increasingly upset as he instructed Tyson to box more rather than just throw bombs, and Tyson refused to follow orders. They argued between the fifth and sixth.

"Kevin was upset with me for not punching," Tyson said. "But I asked him to let me do one more thing, and then I'd listen. I wanted one more round of keeping up the pressure. He {Thomas} was very tired and, although he was taking a great shot, I knew he wouldn't take many more. Kevin wanted me to box. I wanted to land bombs."

Thomas was in superb shape, and he said his idea was to use that, to work Tyson to the body as much as possible and to get through the early rounds intact, and then become more active in the later rounds. But he claimed he was disrupted by a long delay when the thumb on his left glove came loose.

"That broke my strategy," Thomas said.

"Then I got caught with that uppercut."

Perhaps someone with more punches can use the strategy. But for the moment, Thomas doesn't see anyone. Not Tucker, and not Biggs. "No," Thomas said. "Right now Mike's the one."