(CNN) -- Manny Pacquiao became the fifth boxer to win major world titles in five different weight divisions after demolishing WBO welterweight champion Miguel Cotto in Las Vegas on Saturday night.
The Filipino, dubbed "Pac Man", stopped the Puerto Rican in the 12th and final round to boost his claims to be known as the world's best pound-for-pound fighter with a victory in his seventh weight category -- his Ring Magazine and IBO crowns are not universally recognized.
Cotto weighed in at 145 pounds in front a 5,000 strong crowd at the MGM Grand Arena, with Pacquiao tipping the scales at 144 pounds.
The fight began well for Cotto as he delivered several powerful jabs, despite Pacquiao's speed.
But Cotto found himself on the canvas in the second round after Pacquiao struck him with a flash knockdown
Pacquaio followed this in the fourth round with a right-hook left-hook combo, and continued to punish his opponent, who suffered swelling above both eyes.
Cotto lasted until the final round, when referee Kenny Bayless stopped the fight following another onslaught from Pacquiao.
"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.
"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."
It was Pacquiao's first fight since a stunning knockout of Britain's Ricky Hatton sixth months ago at the same venue, having convincingly defeated the legendary Oscar De La Hoya in his previous outing.
Pacquiao, who has won 49 fights, lost three and drawn two, is being lined up for a money-spinning fight with American Floyd Mayweather Jr, who has also won five major titles in five weight divisions.
Pacquiao was rated as favorite by Las Vegas oddsmakers, but Cotto -- who has held a world title every year since 2004 -- had just one defeat in 35 fights with 27 knockouts going into the bout.