Manny Pacquiao was delighted to have claimed another bigger opponent as a victim following his impressive 12th-round stoppage of welterweight title-holder Miguel Cotto in Las Vegas.

The Philippines fighter added the Puerto Rican to big-name, big-frame scalps Oscar de la Hoya and Ricky Hatton taken over the last 12 months when he defeated WBO welterweight champion Cotto at the MGM Grand Garden Arena.

It was another explosive display from pound-for-pound king Pacquiao, who 11 months ago had dismantled de la Hoya over eight rounds in his first fight at welterweight and in May staged a brutal second-round knockout of light welterweight kingpin Hatton.

This time, fighting only his second bout at 145 pounds, the man who started his career at 107lbs marched to the 50th victory of his professional career with his 38th stoppage, the most recent of the 30-year-old's three defeats having come at super featherweight to Erik Morales more than four years ago.

Cotto, whose record now stands at 34-2, had got off to an encouraging start, more than coping with Pacquiao's speed and keeping his rival at bay with a series of strong jabs in the opening round.

Pacquiao found his rhythm soon after, flooring his man in the third with a flash knockdown and then dishing out a clubbing right-hook, left-hook combination to really hurt Cotto in the fourth and signal the start of a comprehensive beating.

The victor said patience had been the key to wearing down Cotto. "I heard that he was bigger than me and stronger than me and that's why I tried to be more aggressive and fight toe to toe and try to [negate] his power," Pacquiao said.

"Our strategy for the fight was not to hurry, take our time, because we knew his strategy was that he was going to counter.

"We were very careful in the early rounds then I controlled the fight and tried to put him under pressure."

Of the first knockdown, Pacquiao added: "I was looking for a knockout shot, that's why I didn't throw a lot of punches. It was timing and in the last minute I hit a good punch with the right hook."

With another knockdown in the fourth behind him, Pacquiao moved further ahead on the scorecards and he said he was increasingly aware that his rival would be trying to summon a last-ditch knockout.

"As the rounds went on I really focused and was careful with my timing because he was looking for a big shot, a one-punch knockout," he said. "I kept pressuring him and was very careful about his counter.

"We tried our best to knock him out because that's what my trainer said. I thought they were going to stop the fight in the 11th round and I was surprised he made it to the 12th round."

Cotto paid tribute to his conqueror and the different angles from which he threw his punches, making it difficult to see them coming. "It really made the difference," Cotto said. "The jabs he throws made a big difference because I couldn't see from where the punches were coming and I couldn't protect myself from those punches.

"I've fought everybody. Miguel Cotto comes to fight the best boxers and Manny is one of the best boxers of all time."

Freddie Roach, Pacquiao's trainer, had taunted the Cotto camp during the build-up by predicting a first round knockout but more seriously suggested the fight would end in the ninth. Yet he had not been pleased with the strong start made by the Puerto Rican.

"I thought we could break him down and if Manny put pressure on him he could get him out of there and he finally did," Roach said. "Early in the fight he was tested with Miguel's power and laying on the ropes a little too much but once he got his rhythm on the fight it was all over."

Roach did concede he had been concerned about the outcome after the opening round. "I was worried because Cotto came out and fought a great fight at the beginning. He was fighting very smart and Manny had to make the adjustments.

"Once Manny used his pace and his movement he had too much speed [for Cotto]. He wasn't using that at the beginning but once he started getting into his rhythm it was no problem."