LAS VEGAS — Manny Pacquiao fought a lot bigger than he looked. Oscar De La Hoya simply looked old.

Pacquiao dominated his bigger and more famous opponent from the opening bell tonight, giving De La Hoya a beating and closing his left eye before De La Hoya declined to come out of his corner after the eighth round.

The fight was so lopsided and De La Hoya looked so inept that it could spell the end for boxing's richest and most marketable star.

It was only the second time in De La Hoya's 16-year pro career that he was stopped in a fight, and it was made even more shocking because it came at the hands of a fighter who fought at just 129 pounds months earlier. At the age of 35 he seemed not only well beyond his prime, but unable to offer any answer to the punches that Pacquiao was landing almost at will.

De La Hoya's left eye was closed shut as he sat on his stool after the eighth round and the ring doctor, referee and his cornermen discussed his condition. De La Hoya offered no complaints when his corner decided he had enough, getting up from his stool and walking to the center of the ring to congratulate the victor.

"You're still my idol," Pacquiao told him.

"No, you're my idol," De La Hoya said.

Two of the three ringside judges scored all eight rounds for Pacquiao, while a third gave De La Hoya only the first round. The Associated Press scored every round for the winner.

The fight was lopsided from the beginning, with Pacquiao landing punch after punch while De La Hoya chased after him, trying to catch him with a big punch. Pacquiao was winning big even before the seventh round, when he was pounding De La Hoya against the ropes in his corner and catching him with huge shots that knocked him across the ring.

De La Hoya remained upright, but with one eye closed and his reflexes seemingly gone there was no chance he was going to land the big punches he would have needed to turn the fight around. Ringside statistics showed Pacquiao landed 45 power punches in the seventh round to just four for De La Hoya.

"He's just a great fighter," De La Hoya said. "I have nothing bad to say about him. He prepared like a true champion."

Pacquiao came up two weight classes to fight for his biggest purse ever, while De La Hoya dropped down to meet him at 147 pounds. Though De La Hoya towered over Pacquiao and had a big reach advantage over him, Pacquiao had no trouble getting inside what few jabs De La Hoya threw to land his shots.

"We knew we had him after the first round," Pacquiao's trainer, Freddie Roach said. "He had no legs, he was hesitant and he was shot."

Roach trained De La Hoya in his last big fight a year ago and said De La Hoya simply couldn't throw punches when he needed in that fight. That was magnified even more against Pacquiao, who not only was as elusive as Floyd Mayweather Jr. but threw punches back that kept De La Hoya off pace.

"Freddie, you're right," De La Hoya told the trainer after the fight. "I just don't have it anymore."

If De La Hoya's career is over, it will be the end of a remarkable story that began when he won the Olympic gold medal in Barcelona in 1992 and went on to become the biggest box office attraction in the sport. But while he sold tickets, De La Hoya hadn't won a big fight in six years, and there were whispers long before the fight that he had nothing left.

De La Hoya not only dropped down to fight for the first time at 147 pounds in seven years, but actually came into the ring unofficially weighing less than Pacquiao. Both fighters got on scales in their dressing rooms and De La Hoya was 147 while Pacquiao was 148 and a half.