This could mark the end of the heavyweight division as we know it.

	Does David Tua have any shot against this man?

World champion Lennox Lewis will dismantle No. 1 contender David Tua Saturday night in Las Vegas. And, if previous warnings hold true, such a result -- whether it's an early devastating knockout or a prolonged pummeling -- will wipe out the old heavyweight guard, leaving a group of unproven youngsters to tussle over championship belts that will become even more irrelevant than they already are.

It might sound like a stretch now, but a decisive Lewis victory could set into motion a chain of events that would deplete boxing's most glorious division of virtually every big name.

There are scant few major heavyweight fights to be made. But one megabout that stands out is between Lewis and Mike Tyson. Both fighters once craved that match, but now each is dealing with the specter of retirement.

Tyson announced he wasn't going to fight after his Oct. 20 fight with Andrew Golota. Now Lewis has gone on record as saying he might walk away from the sport if a bout against Tyson cannot be made.

"Obviously, it is the biggest fight out there for me," Lewis said last week. "I have other options, I can travel around the world. I could fight in South Africa on Nelson Mandela's birthday. But I have to ask myself, 'How big are the incentives without a Tyson fight?' "

Tyson and Lewis need each other. Tyson is living off past glories and requires marquee names to fight, as evidenced by the disappointing pay-per-view and gate receipts from the Golota fight. Aside from a third fight with Evander Holyfield, Lewis is the only major payday remaining for Iron Mike, who could make as much as $30 million.

Lewis, meanwhile, doesn't even have Holyfield to fall back on after their two ugly encounters in 1999. With Tyson the lone name missing on Lewis' application to become the greatest heavyweight of the current era, Lewis has had no other alternative for work than to go after heavyweight prospects.

And if Tyson remains retired, then there's no reason for Holyfield to keep fighting either. He has stated his desire to fight only the major names of his day and not the ho-hum, upcoming generation of heavyweights that includes Tua, Michael Grant and the Klitschko brothers.

The previous roadblock to making Lewis-Tyson was the argument over which cable giant would televise it on pay per view. Lewis has a deal with HBO, while Tyson belongs to Showtime.

After Saturday night, however, the bigger problem will reside within Tyson after he sees what Lewis does to Tua.

Tyson will be watching with much interest as Lewis defends the IBF and WBC belts in a scheduled 12-rounder at the Mandalay Bay Resort & Casino. Tua routinely is compared to Tyson, and not because America Presents promotes them both. They both stand 5-foot-10 and use devastating power to bore into opponents.

Tua's performance, therefore, will provide a barometer of Tyson's chances against the 6-foot-5 Lewis.

And once Lewis dispatches Tua, Tyson won't see much incentive to overturn his retirement.

Lewis is at the peak of his career and brimming with confidence. He destroyed Frans Botha in July, nearly decapitated Grant in April and beat Evander Holyfield twice last year even though corrupt or inept (take your pick) judges scored the first meeting a draw. ESPN.com, incidentally, scored the boring rematch in Holyfield's favor, but Lewis won a unanimous decision on the cards that counted.

Lewis and Tua sport similar records. The champ is 37-1-1 with 29 knockouts, while the challenger is 37-1, 32.

	“	There are bound to be some explosions with Tua's power, and at some point of the fight I expect Lennox to be fighting for his life. I expect Lennox to win, but I also anticipate fireworks. ”
		— Emanuel Steward, Lewis' trainer

But Lewis should go down in history as one of the all-time great heavyweights, while Tua, as talented as he might be, has a reputation based more on hype than substance thanks to America Presents' brilliant marketing efforts. Public relations guru Fred Sternburg has mounted a media blitz that would make the 1986 Chicago Bears blush. Sternburg plays off Tua's colorful Polynesian heritage and makes the engaging youngster highly accessible to the media.

While Lewis, 35, has been fighting elite opponents for years, Tua is taking a serious step up in competition Saturday. Tua, who turns 28 in two weeks, has fought four times the past two years, and three of those foes were pugs named Gary Bell, Shane Sutcliffe and Robert Daniels.

Tua's most prominent foes have given him trouble. Ike Ibeabuchi handed Tua a controversial 1997 decision loss, but it could not be argued Tua's passiveness gave away the early rounds. Hasim Rahman -- a subpar boxer to say the least -- easily handled Tua in 1998. But Rahman, fading late, absorbed a shot after the bell and lost on a 10th-round technical knockout.

Tua obviously has problems handling second-tier fighters. There is no way he can expect to execute against the most masterful heavyweight boxer of this era.

Lewis is a 3-to-1 favorite to beat Tua. The only question is how Lewis will do it.

Despite the seven-inch height differential, Tua probably will come into the ring around the same weight as the statuesque Brit, who likes to fight at a chiseled 245 pounds or so.

The left-hooking throwing Samoan from New Zealand -- who trains in Las Vegas -- resembles a globe. He weighed 253 for his first-round demolition of Obed Sullivan in June and 243½ pounds for his third-round stoppage of Daniels in July.

It will be impossible for Tua to effectively box Lewis, who is quicker and has a 15-inch reach advantage. Tua will have to come to Lewis, and the champ prefers fighters who do. Just ask Botha and Grant -- that is if their brainwaves have cleared up enough yet to comprehend the question.

The only variable to watch for is whether the fighters slug it out inside or become content to hold each other. If it's the former, Lewis scores an early knockout. If it's the latter, Lewis wins by decision.

Tua's squat frame could make him hard to move and knock down, and even if he is the second coming of George Chuvalo in terms of chin, Lewis still should pick the challenger apart.

But that's not to say this fight will be dull. Tua can crack, particularly with his left hook. That factor alone gives him a chance.

Oliver McCall shocked us all in 1994 when he knocked out Lewis. That loss helped Lewis mature into the boxer he is today by teaching him to always be wary of power.

Lewis' trainer, Emanuel Steward, has made sure to spend considerable time teaching Lewis how to clinch Tua. We will find out Saturday night if that strategy is Plan A or Plan B.

"There are bound to be some explosions with Tua's power, and at some point of the fight I expect Lennox to be fighting for his life," said Steward, whose presence only further bolsters Lewis' odds. "I expect Lennox to win, but I also anticipate fireworks."

Tyson should find himself wincing at the glare of Lewis' extravaganza. A potential $30 million purse could induce Tyson beyond any feelings of inadequacy, but the HBO and Showtime hassles might also be enough to scrap any chance of Lewis-Tyson ever happening.

"Whether he wants to take it, after I dispose of David Tua, the opportunity will still be there," Lewis said. "A fight with Tyson would generate a lot of money and, I believe, could make history.

"The public is very keen on it."

As well it should be. Because if that fight doesn't happen, the public won't have much to watch at all besides a group of uninspiring young prospects with losses already on their ledgers.

How about Oleg Maskaev vs. David Izon for the undisputed heavyweight world championship?

Maybe it's time for fans to start retiring, too.

ESPN.com boxing writer Tim Graham covers boxing for The Buffalo News and The Ring Magazine, and formerly wrote for the Las Vegas Sun.