If Roy had retired after Ruiz, then his chin would have been seen as one of the best. Only one kd, that's it. But only two fight after that, suddenly it seemed as if he was shot. Who knows really?
It's one of those things that's a little difficult to measure because Roy didn't take a lot of shots from big punchers during the prime of his career. His reflexes were cat-like and his speed was from another planet. Once he got knocked out by Tarver his punch resistance seemed to be shot to pieces though that's for sure (although age could've played a factor there too). I'd hesitantly say his chin was good but not great.
I think it's likely that Jones was always packing glass and his superior athleticism allowed him to get away with it, ensuring that suspect mandible wouldn't be a factor But it's also true that chins don't get better with age, so clearly that accounts for why Jones took so many canvas naps late in his career
Difficult to say with Jones. He obviously took clean punches on the chin prior to his first KO loss. I think once he suffered his first KO loss it shattered his confidence and he couldn't make the adjustments from relying on fast reflexes and mentally recovering from the KO. I wouldn't say he had a glass jaw, the shots that KO'd him were big punches he didn't see coming or couldn't defend.
Jones took a ton of shots throughout his career and his chin was just fine. Toney hit him. Hopkins hit him and he wasn't staggering around the ring. Maybe he doesn't have a Lamotta type chin but his chin was pretty good. As you age,and it doesn't matter who you are, your ability to take punishment changes and sometimes drastically especially mixed in with a long career like Jones had. You guys act like nobody ever touched him and that is simply not true.
I have said this on multiple threads previously; I just don't think the stats, broken down, bear out that he had a weak chin all along. Separate his career into two ... the first 50 fights (up to age 35) - 1 knockdown in a fight where he got up to win the round: 1 DQ loss. Fights 50 to 76 (aged 35+) multiple KO losses and losses.However fast you are, you're gonna get hit - and he did, even at HW. Logic points to him slowing down, getting older and his chin - and body in general - deteriorating. His real issue, IMO, was staying on far, far too long. Jones aside, I always think it's pointless to compare ageing fighters to younger ones. Most boxers, if they go on into their 50s, are gonna lose multiple times and probably lose badly. Best to compare the older Jones to the younger one and the answer is obvious; they are two different fighters.
It was always weak but he was adept at hiding it. Lou Devalle who wasn't a puncher at all dropped him like a sack of spuds.
You dont have a record like that with a glass chin. But Jones played a lot of dodgeball at 168 and missed the better fighters. And for that, he gets a good but not great score
Roy was slippery in his prime. He wasn't hit cleanly too often. He did get caught at times and his chin appeared solid. I recall James Toney timing Jones with some right hand counters that he took well. The one bout that Roy took some punishment was Tarver 1. Roy showed heart, grit and a chin for 12 rounds. I don't think he could have done that if he was hiding some fine China in his chin.
Tarver hammered him with some solid shots in their first fight and Roy took them. I always felt that the first Tarver fight really took a lot out of him and he was never the same again. Chins can degrade over time if you constantly get hit hard and i think his chin was cracked against Tarver the first time, then shattered the second time.
I think prime RJJ's chin was neither granite nor glass. Posters are correct to point out his stoppage defeats came past prime, post the age of 35. The other factor to consider is that RJJ was a natural SMW, getting stopped at LHW and CW. Aside from perhaps Johnson, all his stoppage losses came against naturally bigger men. Being way past prime, late 30s/40s, reflexes dulled, facing naturally bigger men, all contributed to his vastly increased rate of getting stopped.