Honestly, if you aspire to be a top tier boxer I feel like "chin" or punch resistance is nowhere near as important as people on here make it out to be. Most top P4P boxers lately had very little use for a fantastic chin because their abilities kept them from getting hit. Think Ward, Wlad, Mayweather, Rigo, Kovalev and so forth. These guys barely ever eat flush shots (there is virtually no intel on whether Ward's and Floyd's chins are good or not because it doesn't matter). Everytime I see people predict outcomes in fights in which a chinny skilled boxer fights a slightly less skilled but hard hitting guy, the guy with the heavier hands is favoured by the majority.
It is important, because every boxer that really has to defend against all comers will need a chin. Can you imagine Ali with a bad chin? Would anyone have called him a goat if he had? Don't think so.
Hearns, Leonard, Duran and Hagler were not top tier boxers? Because they sure as **** beat the **** out of eachother.
Faerun has a point, in which a bad chin can be protected and a fighter can still have an excellent career despite that. Wlad who has an average chin at best, did so. Lewis' chin was nothing to write home about, and he also did very well. But, a good chin always helps.
It's boxing, everyone gets hit eventually. Especially as you move up in competition. I can't think of one great boxer that didn't have at least an adequate chin.
Does any ATG have a mediocre chin? Lewis? Louis? Who else? Not so sure about Louis though, he did get KD but not KTFO.
Come on man, even prime Roy Jones got nailed occassionally....... you gotta be able to take a good shot or in the long term you're going nowheres.