Sometimes it's easy to tell who the naturally bigger man is in a boxing match.

Last Saturday, England's David Haye lifted the WBA heavyweight championship from Russia's Nicolay Valuev on a 12-round, majority decision in Nuremberg, Germany. At 6-3 and 217 pounds, Haye looked like a ventriloquist's dummy alongside the 7-foot, 316-pound Valuev.

But the matter of who holds the advantage in size and strength -- in quickness and punching power, too -- is not always immediately or visually apparent. The fighters might be of similar height and weight, but that parity might not hold up upon closer inspection. Packing weight onto a smaller man might make him his opponent's equal on the scales, but not necessarily in the ring.

Which brought us to the most-anticipated matchup of 2009, last night at the MGM Grand in Las Vegas, in which WBO welterweight champion Miguel Cotto (34-1, 27 KOs), of Puerto Rico, defended his title against international sensation and man of many belts Manny Pacquiao (49-3-2, 37 KOs), of the Philippines. The contract weight was 145 pounds, two below the welterweight limit.

Should Pacquiao win the pay-per-view showdown -- and the chameleonlike southpaw was nearly a 3-1 favorite to do so -- he would make history as the first fighter ever to win world championships in seven weight classes. Considering that the 5-6 1/2 "Pac-Man" began his career at a mere 106 pounds, his ability to maintain peak proficiency as he's climbed the ladder is remarkable. Even more impressive is the fact that Pacquiao's intense training and nutritional regimens enabled him to put on all those additional pounds while retaining his trim, athletic physique.

Freddie Roach, a three-time winner of the Boxing Writers Association of America trainer of the year award, made Pacquiao almost sound like a comic-book superhero.

"Manny is a throwback," gushed Roach, who predicted that Pacquiao would win by first-round knockout. "He is like Henry Armstrong (the late Hall of Famer who once simultaneously held three world titles in different weight classes).

"But the amazing thing is that he's carrying his power with him along with his speed. He is passing people like Sugar Ray Leonard and Tommy Hearns, who were six-division world champions."

Pacquiao seemingly answered most questions about his ability to compete at a much higher weight when, last Dec. 8, he retired future Hall of Famer Oscar de la Hoya by making him quit on his stool after eight one-sided rounds. That was Pac-Man's first fight at welterweight.

Moving back down to junior welter, Pacquiao followed up his mastery of De La Hoya on May 2 with a spectacular, two-round knockout of England's Ricky Hatton, who had said his superior strength would enable him to impose his will on Pacquiao.

But the 5-7 Cotto, who turned pro as a lightweight, has been a champion at junior welterweight and at welterweight. By consensus, he is one of the world's top five or six pound-for-pound fighters. And, he insisted, he is not prepared to step aside for any former flyweight who has to gorge himself at the dinner table to beef his way up.

"If he thinks he is going to win seven titles in seven weight divisions now, he has picked the wrong moment, the wrong fight and the wrong opponent," Cotto said.

But what of Pacquiao's presumed speed advantage?

"He's a fast fighter," Cotto acknowledged. "We know he has speed. We know he has a style, and we are prepared to beat it. You'll find out on Nov. 14 how I am going to deal with his speed."

Those who favor Cotto say he's in his prime, which De La Hoya was not, and that he is a better, more well-rounded fighter than Hatton. There also is a lingering sentiment that Pacquiao might be exceeding the limits of his body.

"He is coming up from a lower weight division, and if he thinks he is going to have the same power as Miguel Cotto, his thinking is very wrong," Cotto said.

Even Roach does not dispute that Pacquiao might not always be able to eat to defeat ever-larger men.

"For him to fight at 147, we have to feed him five times a day to keep the weight on," Roach said. "I think (welterweight) will be his final stop, but you never know."

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