Juan Manuel Marquez knocked Manny Pacquiao out with a right hand midway through their fight in Las Vegas, handing the Filipino star his second straight defeat.

Pacquiao had first touched the floor in the third round but knocked Marquez down in the fifth, and the two went into a heavy exchange in the sixth round. Marquez then threw a right hand that flattened Pacquiao facedown onto the canvas just a second before the end of the round.

The haymaker left Pacquiao floored for two minutes before his team managed to get him up.

By that time, Marquez was already celebrating his triumph in front of the sold-out crowd at the MGM arena, which not surprisingly favored the Mexican boxer heavily.

Ringside punching stats showed Pacquiao landed 94 of 256 punches, to 52 of 246 for Marquez. But it was the last punch that made up the difference, knocking Pacquiao out for the first time in Marquez's 17-year professional career.

“He was in charge,” Pacquiao's trainer Freddie Roach said. “He just got a little too careless and got hit with a punch he didn't see.”

Promoter Bob Arum immediately said he could see a rematch ensuing, which would be the fifth fight between the two boxers.

“Why not?” Packman said.

Aside from Bradley's previous loss by split decision, this was Pacquiao’s first defeat since 2005, when he lost unanimously to Erik Morales. His match against Marquez was the third time he suffered a knockout and a TKO.

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