Jose Luis Castillo, left, lands a stinging left hook to the head of Diego Corrales 47 seconds into the fourth round to earn a knockout victory in the fighters' much-awaited bout Saturday night at the Thomas & Mack Center. Castillo was ahead on all three judges' cards at the time. Photo by K.M. Cannon. Diego Corrales, left, absorbs a left hand from Jose Luis Castillo during their bout Saturday night. Photo by ISAAC BREKKEN/REVIEW-JOURNAL Diego Corrales struggles to get up after being knocked out by Jose Luis Castillo in the fourth round as referee Joe Cortez count him out at the Thomas & Mack Center on Saturday night. Photo by K.M. Cannon.

Jose Luis Castillo had a rough day on Friday trying to make the lightweight division's 135-pound limit, but it was Diego Corrales who paid the price Saturday night.

Castillo dominated the rematch of their hyped May 7 fight, widely regarded as among the best in history.

There was no such drama before a deafening pro-Castillo crowd at the Thomas & Mack Center, as Castillo knocked out Corrales with a devastating short left hook 47 seconds into the fourth round.

Castillo won each of the three completed rounds on two of the three judges' cards. He opened a cut on Corrales' right eyelid in the second round, staggered him and nearly put him down in the third before sending him down for the count in the fourth.

"I knew he wasn't getting up," said Castillo, who weighed 147 pounds at a 3 p.m. weigh-in Saturday, a little less than six hours before he went to the ring.

He had to weigh in again Saturday after failing three times failing to make the 135-pound limit on Friday. Because he failed to make the weight, neither of Corrales' world title belts were at stake.

That didn't matter much to Castillo, who had made a $100,000 bet with Corrales promoter Gary Shaw at the afternoon weigh-in.

After referee Joe Cortez reached the count of 10, Castillo raced to the ropes and shouted at Shaw, asking for his money.

Shaw said he had written a check at the weigh-in, but said Castillo manager Fernando Beltran told him there would be no bet.

Castillo, who also was fined $120,000 for failing to make weight, said he took the fight more seriously than he did their first one, which Corrales won by 10th-round stoppage.

Castillo said he had trained less than a month for the first fight.

"I trained seven weeks for this fight," Castillo said. "For the first fight, I trained just three weeks."

The difference showed, as Castillo was sharp from the outset. He ripped Corrales with a left hook just seconds after the opening bell and consistently got his right hand in.

Castillo said he was embarrassed by the fiasco at the weigh-in, which included an attempt by his physician to cheat.

But he said he hurt a rib in training on Sept. 28 and had to return to Mexicali, Mexico, to be examined. He was told he bruised cartilage in his rib on the right side.

Corrales said he would invoke the rematch clause, which Castillo was only too happy to accept.

"If they want to make this like the Rocky movies, I'll fight him five or six times," Castillo said. "I don't care."

Corrales, a Las Vegan who earned a career-high $2 million plus a share of the pay-per-view profits, said though he appeared hurt at the end of the third round, it didn't bother him in the fourth.

"I was OK after the (third) round," Corrales said. "He caught me with that last shot. I have no excuses. I don't want to take away from the win."

Shaw, though, was less than happy. He second-guessed himself for allowing the bout to go on as a non-title fight.

Corrales, he said, was at a disadvantage even though he unofficially weighed 149 pounds at 6 p.m.

"One guy had to sweat to make the weight and the other guy didn't because he didn't give a (care)," Shaw said. "I will never do this again. If it happens, you'll see my ass in the airport in two hours."

Shaw said the rematch would be at 135 pounds.

Castillo, though, wasn't thinking of such things. He was happy he was able to fulfill a promise he made to his camp members earlier in the week.

"I told everyone I'd knock him out before seven rounds,'' Castillo said. "I made that promise and I lived up to it."