Over at the Circus Circus casino they've got this game called Whack the Mole, which is what many feel Larry Holmes would like to do to Michael Spinks.

When Spinks defends his International Boxing Federation title Saturday night at the Las Vegas Hilton Center, it will be just one small part of the entertainment, what with Frank Sinatra due in any minute and Dean Martin also around for a few va-va-va-vooms. Especially here in Las Vegas, a town that only comes out at night.

The Strip may need a dust rag, but there is nothing like a couple of headliners and a world heavyweight fight to enliven things. Start with Holmes, who suddenly has broken his six-week silence.

"I'll turn it into a wrestling match if I have to," said the former champion turned sullen challenger.

It has been seven months since Holmes had his IBF title taken from him by Spinks, the once-spindly light heavyweight with a head for strategy. Spinks' victory by decision was a humiliating one, for it made him the first light heavyweight to dethrone a world heavyweight champion and it prevented Holmes from making history by tying Rocky Marciano's record of 49-0.

Spinks (29-0) did it by burrowing down in the ring and outpointing Holmes with his unorthodox style, elbows flapping. When the two meet in the rematch Saturday at 10:30 p.m. (EST), Holmes will have none of it. This time, he says, Spinks goes down in seven.

"I had been slacking off and it took someone like Michael Spinks to wake me up," Holmes said. "Last time it was a distance fight. This time it will be close. I'll take punches if I have to. I've been soaking my skin in salt water to make it tough. If he runs, I'll grab him."

Holmes weighed in today at 223 pounds, 1 1/2 pounds heavier than last September. Spinks has grown to 205, five pounds heavier than he was last September and 30 pounds heavier than he was as the light heavyweight champion.

Overall, Spinks looks perhaps slightly more fit, and that could be a difference. Holmes' most obvious shortcoming in September was his lack of speed. He lost the decision primarily because he didn't throw enough punches. At age 36, Holmes may lack the swiftness to stay with Spinks in what could be his final professional fight. According to Holmes' camp, however, he hasn't lost his hand speed; he is merely "conserving his energy."

"Everything Larry did last time worked," trainer Richie Giachetti said. "He just didn't do enough of it."

The September meeting was an uninspiring bout, what with Spinks circling and throwing a few wild combinations and Holmes looking as though he were wearing a seat belt.

What seemed to be particularly frustrating for Holmes in September was the idea that he had been outsmarted. The Holmes camp has spent much of the week trying to push him into a different sort of fight.

"Spinks didn't fight," Giachetti said. "Boxing is reducing your man to submission. It's not running around, throwing three or four crazy punches and running again. That wasn't strategy; he was scared and running. If Spinks wants to be the champ, let him fight."

Spinks almost certainly will make Holmes stalk him again, but he may not be as afraid of Holmes' power as he once was. That alone could make for a better fight. His 205 pounds suits him; his legs are stronger and so is his upper body.

"I outsmarted Larry last time," he said. "I used my knowledge to beat him. I circled him and made it difficult for him to hit me . . . Every light heavyweight who has gone up against a heavyweight has been afraid. I'm not. He's going to come in with everything he's got. He's going to try to tear my head off. I've got to do the same.

"I'm not going to run from Larry. I'm just going to wait to take my shot. I'll try to bait him into making the mistake I want him to."

Despite being the champion, Spinks is considered the underdog, but that is not particularly surprising; in the last fight, many wondered whether he would last more than one or two rounds. In fact, he is perhaps more comfortable in that role.

"It makes me feel good," he said. "Last time I was an even greater underdog. I haven't gotten high-minded. I'm not an awesome champion. Larry said last time he felt sorry for me; he didn't want to knock me out in front of my family. Well, I'm the defending champion now, Larry's angry and he doesn't have to feel sorry for me anymore like he did."