Manny Pacquiao (right) had to take considerable punishment
Manny Pacquiao emerged triumphant in a thrilling and bloody WBC super featherweight title clash with Juan Manuel Marquez in Las Vegas.
Though Marquez landed more punches at a higher percentage, Filipino Pacquiao knocked down the Mexican in round three to claim a narrow split decision.
But both fighters, who were meeting for the second time, thought they had won.
"I still feel I'm the champion," said Marquez, who had won the belt last year by beating Marco Antonio Barrera.
Judge Duane Ford favoured Pacquiao 115-112 and Jerry Roth called it 115-112 for Marquez, while Tom Miller gave a 114-113 edge to Pacquiao.
When he cut my eye in the fourth round, he made it more difficult for me
Pacquiao, who was winning a major world title in a third weight division, ruled out a third clash with Marquez, saying: "I don't think so. This business is over."
The first meeting between in 2004 ended in a draw.
Pacquiao said he intended to move up another division for his next fight against David Diaz, the WBC lightweight champion.
The action was fast and frenetic froim the opening bell at the Mandalay Bay Events Center.
Marquez staggered Pacquiao in the second round, but Pacquiao floored Marquez in the third with a left hook.
Pacquiao then wobbled Marquez again late in what is sure to be one of the year's best rounds but could not finish off his opponent.
Marquez cut Pacquiao with a punch in the fourth round, but Pacquiao staggered him again in the seventh, and a collision of heads opened a nasty cut near Marquez's right eye.
Marquez then split Pacquiao's right cheek early in the eighth, but Pacquiao kept charging forward to take punishment with his obscured vision.
They traded quality punches until the final minute, when Marquez landed a handful of combinations to do the final damage.
"When he cut my eye in the fourth round, he made it more difficult for me and I couldn't take control of the fight," said Pacquiao.
His trainer, Freddie Roach, added: "It was a close fight, but we came back at the end. It could have gone either way."