As Durán's athleticism began to fade he made technical improvements that enables him to stay atop of his game. His consistency and dedication let him down though. Realistically, up until 1990 he shouldn't have been defeated by anyone barring fellow members of the fab 4.
Leonard in Montreal was younger bigger and faster, this was the best version of Ray Leonard that I ever saw.........and he lost.
I have to say that at 135 lbs, Roberto Duran was at his very best, 1972-1979. He looked trim, lean and mean. His fighting skills improved especially after he won the title. his passion for the sport increased, he had trainers and management that were very experienced, so he had to prepare at a higher level. In the ring, he had what Joe Frazier would later remark, He Had Eyes Like Charles Manson. He was not a braggart like today's fighters. But as champion, he was tested by very good quality challengers, Esteban De Jesus, Ray Lampkin, and Vilomar Fernandez, who owes a decision over the great Alexis Arguello. After weight problems and urging by the media, he caved into demands to step into the next weight classes, 140 lbs, and 147 lbs, then higher weights where he looked out of shape. The hunger was gone except for at the dinner table.