The referee should've had his licence revoked after that one and never allowed anywhere near a ring again.
It is sadly comical when people try to argue Don King was good for boxing. He should of been exiled inducted into the HOF
It was a career of taking shots that did the damage but towards the back end of his career he was taking way too many flush punches in bouts. Against Shavers he was eating monster right hands all night long, how the hell he managed to do so I'll never know.
I would say Frazier 3, Norton 3, Shavers, Spinks 1 and then Holmes where he took battering that would have koed an ordinary fighter is what dramatically hastened his physical condition. That's allot of punches taken in five bouts over a 5 year period. Ali should have retired for good after his third bout with Frazier.
Not all olympic champions punch hard, Howard Davis was considered the best fighter at the 1976 olympics but couldn`t punch hard enough as a pro, I doubt Audley Harrison would have done the same damage as the aggressive Spinks.
I think it was the sparring; granted, the fights were all-out wars and slugfests. But the hundreds of rounds spent getting hit - and Ali admittedly (after the exile) spent a lot of time on the ropes believing that, since he was seldom hit in his younger days, he could "learn" how to take punches better if he let sparring partners tee off on him - had to take their toll. If you look on Youtube, there's a clip of Cus D'Amato and Angelo Dundee watching Ali spar, and Cus' concern over his taking so many punches; Angelo explains the so-called logic above at play. My only issue with Dundee was his frequent reluctance to be more assertive with Ali; Cus would have been more stern. But Ali - who nonetheless respected D'Amato - would never have listened anyways. PS: Here's the clip - footage noted begins at 7:10 This content is protected
Ali called Frazier just before he died and asked him to forgive everything he said to him with his big mouth because he was just trying to sell tickets, Ali was said to be completely quiet away from the cameras, he was also really shy of women in his late teens according to a brilliant biography.
I know it was relatively early on compared to some other fights mentioned. But to me, Frazier 1 had to be a very damaging fight. He took a hellacious amount of huge punches that would've KO'd or killed some men. It was amazing he even made the final bell. To me, that was a peak Frazier, and he had more zip on his punches than he did in No. 3. Who knows really, as McGrain said, it's likely sparring was the main culprit, but I can't help but think that Frazier 1 must've been bad for him.
The shots Earnie hit him with in their fights had to do some major damage. They are very frightful to look at.
I would say it was the sparring especially late in his career. Ali`s weight fluctuations along with the rope a dope tactic. It`s like Ali found a new toy in the Rope and Dope and then he realized he didn't need to get his weight down as much as he could just lay on the ropes. He allowed sparring partners to pound away at him. I believe when a fighter takes beatings when he is out of shape it compounds the damage. Riddick Bowe may be an example. The actual fights themselves have to be the Joe Frazier fights. All three of them. Manila damaged both men.
Lowered testosterone is often a by product of traumatic brain injury so you a bit of a chicken and egg conundrum with Ali's difficulties later in his career.