How much credit do you give Cotto for his win over Martinez?

According to haters from Peasantville USA, Cotto beat an old Sergio. Anyone else with a brain knows ANY version of Sergio steps into that ring, Cotto destroys. Are we to believe that margarito the journeyman knocking Sergio out can do something Cotto can't? Come on now. Plaster heroes are not on the level son.