Miguel Cotto won the vacant WBO junior welterweight title Saturday night, stopping Kelson Pinto in the 6th round. Cotto dominated Pinto, punishing him with left hooks throughout.

The knockout came at 2:28 of the 6th round. After going to the canvas, Pinto beat the count, but was clearly hurt and his corner stopped the fight. It was the first loss in 21 fights for Pinto, who had defeated Cotto twice in amateurs bouts. Pinto was knocked down twice before the sixth — in the 2nd and the 5th.

In the undercard title bout, Daniel Santos retained his WBO junior middleweight title in a split decision over Antonio Margarito.

Margarito was aggressive in the opening rounds, exchanging combinations with the champion and bringing the crowd to its feet in several occasions.

After an accidental headbutt in the sixth opened a cut on Margarito's left eyebrow, the Puerto Rican became more aggressive and dominated the final rounds.

The fight was stopped after the ninth round because of a cut over Margarito's left eye, and the judges gave the fight to the Puerto Rican.

Two judges saw the bout 86-85 and 87-84 for Santos (29-2-1), and the other had it 86-85 to the Mexican.

The Associated Press reported it had Margarito  winning the fight 87-86 at the time of the stoppage.