Manny Pacquiao staged another stunning victory over a bigger man as he took apart Miguel Cotto with a 12th round stoppage in Las Vegas.

It was another explosive display from Filipino folk hero, who 11 months ago had dismantled Oscar 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 Ricky Hatton.

This time, fighting for only the second time 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, 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.

There was more of the same at the start of the second but Pacquiao gradually found his rhythm and began to find Cotto, 29, with big left leads that were landing with increasing frequency as the round wore on.

Cotto caught his man with a big left hook after getting Pacquiao against the ropes for the first time in the fight but the Filipino ended the second on top with a series of stunning combinations as the Puerto Rican mixed it with his rival a little more.

Cotto returned to a more cautious jabbing mode in the third but nothing could have stopped a lightning fast right hook to the head that caught him off balance and sent him to the canvas for the first time.

Cotto appeared unhurt and finished the round strongly, landing a vicious upper cut through Pacquiao's gate followed by a stinging left hook.

The fourth saw Pacquiao open with a barrage that only seemed to encourage Cotto, who finally pinned his rival on the ropes for a sustained period of the round.

Yet when Pacquaio came off the ropes he did so emphatically, turning Cotto and then knocking him down with a clubbing right hook, left hook combination that definitely hurt the Puerto Rican.

Cotto survived and enjoyed a comeback in the fifth, hurting Pacquiao first with an upper cut and then with a left hook, following up in the sixth with another left hook that the little man merely acknowledged with a grin, following that with straight left that rocked his opponent, Cotto responding with another big left of his own only to see another smile in response.

From then on, it was all Pacquiao, dishing out punishment on the Puerto Rican seemingly at will, Cotto replying only sporadically as both eyes swelled over the seventh, eighth and ninth rounds, perpetually kept on the back foot by the relentless PacMan.

The 10th saw Pacquiao give Cotto something of a breather but the writing was on the wall, Pacquiao controlling the rhythm and pace of the fight as his opponent backpedalled throughout.

The 12th and final round saw Cotto quickly in trouble again as Pacquiao resumed the onslaught, referee Kenny Bayless finally bowing to the inevitable as the Puerto Rican was backed into a corner and stepping in to end the contest.