LAS VEGAS -- Two polite and unimposing heavyweights are fighting Thursday night for the championship of the world. One of them is rather large, the other quite small. This is a clue on how to bet.

The challenger and favorite is Evander Holyfield, a sorrowful-looking fellow with a sharp, chiseled face and a sculpted body that shows the efforts of a task force of aerobic instructors, bodybuilders and even ballet teachers. A 178-pound Olympian in 1984, a 190-pound champion in 1988, Holyfield offers himself now as a 212-pound heavyweight.

"I think how it'll be," he said, "when people say: 'He's Evander Holyfield, the heavyweight champion of the world.' I've given more thought to that than almost anything."

At the Olympics in Los Angeles, Holyfield was disqualified by a Yugoslav referee for cooling a New Zealander on the break. Evander's reaction was to show no reaction, which has been his style ever since.

Financially, that distinctive loss separated him from a gang of American winners, forgotten men such as Los Angeleno Paul Gonzales, who had a way with words and was named fighter of the tournament. "I grew up about two miles from here," Gonzales explained memorably, "depending on the traffic."

Holyfield is less loquacious. Asked for a listing of his assets, he responded: "My footspeed, my handspeed, my quickness, my courage." He might have included his trainer, Georgie Benton.

Benton, the only authorized voice in Holyfield's crowded corner, was one of those Philadelphia boxers of legend if not lore, a middlewight. He gave good and scientific accounts of himself against dangerous people like Joey Giardello and Benny Briscoe. Benton values cunning over courage, but understands that some fighters need to bounce their foreheads off fists and that Holyfield is one of those.

"He gets hit with punches from time to time," Benton allowed, "because he's a warrior. Still, he's a better defensive fighter than people think. I like working with him because he's always the same guy. He's like ice water. He stays frigid all the damn time."

James "Buster" Douglas, the champion and underdog, is always a different guy -- the one who overwhelmed Mike Tyson, the one who underwhelmed Tony Tucker or the one who whelmed Steffen Tangstad.

"I'm just like a big diesel Peterbilt," he said, using the truck-stop vernacular of Columbus, Ohio. "It takes me a while to get my pipes warmed up."

It has taken him until 30, through four losses and a draw, to get to the banquet. In the eight months since he razed Tyson in Tokyo, Douglas has dined out on a title like no epicure since Archie Moore.

"I ate harder than I ever worked," Buster admitted. "After that fight, I went over to Grandma's house, kicked my feet up on the back porch and ate pinto beans and chicken necks. Yummy."

He plumped out into a gingerbread man and, while he has reduced lately, still shows a little yeast in the tail. If Douglas comes in under 235, his camp has promised to endow a cathedral.

"I'm in pretty darn good shape," Douglas contended. "If I was worried about how people perceived me, I wouldn't be champion."

Measuring Douglas from across the room, Benton agreed: "A good fighter doesn't give a damn what anyone else thinks. Being an underdog could work for him. Some guys get better with the title."

Benton imagines (and hopes) Tyson represented a singular objective for Douglas, a chilling motivation that cannot be duplicated.

"Buster might have been stronger because his wife left him and his mother died," Benton said. "Sometimes you just say, 'What the hell?' You don't give a damn, so you shoot your load. Can he muster all that up again? He don't know. We don't either."

Undefeated in 24 fights for money, not all of them what you would call professional, Holyfield has to go back 11 years to recall what it feels like to be knocked down. He was 16. One Jakey Winters, back in Georgia, accomplished this feat. It still surprises Holyfield to think how much more peaceful, less humiliating, that experience was than he had feared.

"Preparing for a fight," he said, "I get the same feeling I've been getting ever since I was 8 years old. You never become used to it. But you learn how to deal with it. I'm dealing with it now."

As Benton said, "The smaller man {6 feet 2 1/2 vs. 6-4} with the shorter reach {77 1/2 inches vs. 83} has to figure a few things out right at the start. You know, how deep is the water you're in? But once a man reaches 165 pounds, he can fight anybody. It's been proven. Doc Kearns used to say that."

However, even for a boxing manager, Kearns was unusually resourceful. "Give Doc 2,000 pounds of steel wool," Moore once said, "and he'll knit you a stove." And, speaking of stoves, he never stole one that was still hot.

Douglas and Holyfield seem to be decent men and they may make a decent fight. But this production misses a touch of Kearns or something. One of the undercard fighters refers to himself as Sir Jabalot. Otherwise, everyone concerned is fairly dull.

Barney Nagler, a wonderful old turf and boxing writer for the Daily Racing Form, would have hung around for a great fight. But he died Monday night. It's just a fight.