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Mexican rising star Saul "Canelo" Alvarez retained his WBC super welterweight title by dominating "Sugar" Shane Mosley in a 12-round unanimous decision.

Alvarez (40-0-1), who made his fourth title defense, sustained a cut above his left eye due to an accidental headbutt in the third round. Blood streamed down his face, but he was well ahead of the scorecards throughout the bout and piled up a 119-109 margin from two judges and 118-110 from the other to win going away.

The bout was on the undercard of the Floyd Mayweather Jr. fight against Miguel Cotto.

The 40-year-old Mosley (46-8-1), who was coming off a unanimous decision loss to Manny Pacquiao, was clearly the slower boxer. He landed only 25 percent of his punches to 52 percent for Alvarez.

Although Mosley has never been knocked out in his career, this may have been the end to a long run for the former three-division, six-time champion.

The 21-year-old Alvarez landed a solid left hook in the second round and consistently slowed Mosely with good body shots.