Duran by mid round or early knockout - Cotto is a great young fighter who punishes his opponents relentlessly to the body, but he is no defensive slickster and at 140, his chin was somewhat shaky. Cotto's come forward, pressure style would play right into Roberto's hands. Duran had more variety and was a much more complete fighter who would do everything better. He had the chin and the toughness to take what Cotto would dish out (and the defense not to get hit very much) and he would find the mark and have Cotto badly hurt and unlike Ricardo Torres, he would follow up and stop him. This matchup is like saying who would win? Pernell Whitaker or Zab Judah? Like this matchup, there are some similarities, but overall, the past fighter and the current fighters are miles apart.
Duran, and the reason is that everything that Cotto does well, Duran does better (possible exception; body punching). That doesn't bode well.
Duran. Cotto's career is still in its fledgling stages, but he was clearly green and possibly weight drained at 140.
At 140 you got to go with Duran. Cotto was drained at 140. He was not as strong, as fit or as sharp. It would be about as brutal a fight as physically possible but Duran would define himself down the stretch, maybe enroute to a stoppage. At 147, Cotto may show that he would be Durans superior.
Duran was arguably at his physical peak between his lightweight reign and the first Leonard fight. Cotto looks good and may get better, but for the moment he is a couple of levels below this version of Duran. Duran TKO12