Lower weight fighters who simply didn't have the durability at higher weight classes. Bob Foster, of course. But 40 pounds is a lot of weight to give up.
Ricardo Mayorga isnt a great fighter.Though he had great durabillity at welter,his punch resistance went down when he went up higher in weight
Carlos Zarate never regain the invinciblity he had at bantamweight once he moved into the "feathers".
ricky hatton (not an ATG) but a good example Sugar Ray Leonard was not as durable at the higher weight classes
I'll throw in a little smokey. Wilfredo Gomez, it seems, was not the killing machine at Feather that he was just one division below. Fair enough he had the misfortune to be facing a couple of absolute greats but he still went from a KO nightmare to getting stopped himself. I actually thought despite his terrible start Laporte could have put forth a much much more lively effort. I'm prolly being tough here, Sanchez is a legend and Gomez was declined when Azumah (himself great) took him. Just thought i'd throw it out there. I'm a huge Gomez fan.
Being a bit hard on Bob Foster i feel in these threads as he only lost twice in a 12 year period. To a peak Joe Frazier and then Ali. Before that in 1965 he lost to Zora Folley on points. Put any light heavy in those fights and see if they do any better. Ofcourse it's gonna be hard for any light heavy in history to defeat Frazier or Ali. I feel he was fighting in heavys best era and probably didn't want a part of Foreman, Norton, Lyle, Quarry and the likes.