"He's ready to quit," trainer Roger Mayweather told his nephew after the sixth round.
But Cotto was relentless, coming forward and hitting Mayweather with good shots to the head. Toward the end of the eighth round he landed several punches to the head, prompting Mayweather to shake his head as if they didn't hurt, but by then Mayweather was bleeding from the nose and looked like he had taken some punishment.
Punch stats showed Mayweather landing 179 of 687 punches to 105 of 506 to Cotto.
Cotto, who fell to 37-3, was guaranteed his biggest purse ever, $8 million.
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