Roberto Duran was to relentless, too macho. Mayweather is great by todays standards, but Duran is great by universal standards. The talent pool today is so shallow it makes average fighters look good, and good fighters look great.
People do not understand what Chavez could do fighting 3 inches away from his opponent. A true master at infighting, imo he was the best ever.
Duran by Decision. Floyd is smart enough not to get KTFO unless Duran hurt him bad with one punch, which I dont think he would. At least not a KO punch. Floyd at 135 didnt have enough pop to Keep Roberto at bay. Duran would be just too much For Floyd who needs space to work and a guy in front of him that he could freeze on the end of his punches. Duran was aggressive but not wreckless and Floyds Potshots would do nothing but encourage Duran that he could land his own punches and he would be putting them toghether on Floyd. At 135 Floyd did put his punches together better himself, but Duran would punch between his fast punches and have Floyd backpeddalingg after 4 rounds and resort to playing safety with his jab and footwork. He would survive but not win.
Duran is no Shane Mosley. Shane Mosley might not have had the smarts to figure how to finish a hurt Floyd, but Duran is totally a different monster.