Yep, main problem was that Tyson wasn't the complete boxer. If he had maintained any real longevity in the sport, his biggest problem would always be that any decent boxer who could get to round five had a good chance of beating him. The fact that he was more or less spent after a few rounds dictated his aggressive style - it wasn't purely out of choice. This has been qualified by his coach, and others that trained and sparred with him.
Essentially, he'd need to take Ali out real quick. However, the one major problem here is that he'd be trying to hit a guy with one of the toughest chins in the business. Counter that with the problem that Tyson has a notorious weak chin (albeit it's not been overly tested), then Ali gets the nod from me on this one.
Tyson wasn't a complete boxer? Had a weak chin? Was spent after a few rounds?
Mate, are you serious?
During Tyson's peak from 1985-89 he was a phenomenon.
How great is the depth of your interest/knowledge in boxing?
During that period, Tyson was at his peak. That was prior to his mental and emotional breakdown/decline following the death of his adoptive father Cus D'Amato, and then the death of his second closest mentor/father figure Bill Jacobs, and then the binning of his long time trainer Kevin Rooney under the influence of Don King and his money grabbing missus Robin Givens. After that he signed for the snake Don King and lost the glue that was keeping his life together, he never took the sport seriously again. His entourage grew with numerous clowns and hangers on, he didn't take his training seriously, he neglected his technique, and he believed his own hype. He fell out of love with the sport. Everything was downwards after that fight with Michael Spinks.
If you're to assess him as a boxer you have to do so during the period of his career between 85-89.
The boxing novices and casual fans don't appreciate it, but his technique was close to flawless. His hand speed was unrivalled for a heavyweight. And all of those punches had knockout power, left and right. His body punches, his combinations, the way he was relentless with his pressure and never took a backwards step.
He was exceptional at slipping punches, his head movement was excellent, he could switch to southpaw and lead with his right hand. He made you miss and punished you with brutal counter punches.
People miss all that because all they see is his aggression, they fail to recognise his ability as a boxer.
You don't unify the heavyweight division before your 22nd birthday if you're a shit boxer and just a bully boy brawler with no technique. Anyone who thinks of Tyson that way clearly doesn't have much of an understanding of the sport, frankly. He was a stocky 5'10", with average technique he'd never get close to achieving what he did against bigger and more rangey fighters.
Anyone who thinks he had a weak chin, likewise. Short of a clue. When we was well past it he had Lennox Lewis pinging haymaker after haymaker off his head for circa 6 rounds, and took until the 8th to stop him. It's something Lennox commented on post fight, he was surprised he ate the punches he did, and kept coming.
As for the fitness point, during that peak period he went the full distance several times and won them all via unanimous decision. It's a nonsense of a point.
He was an exceptional fighter, and will undoubtedly go down as a hall of famer.
As for Tyson vs Ali, both at their peak? Probably Ali, but then Ali was beaten by Frazier close to his peak, and Tyson (at his peak) was the much more well rounded boxer than Frazier. His hand speed was greater, he was better at slipping punches, he was stronger and more powerful as well.
It's not as straightforward as saying Ali would walk it, I don't think he would, and there's a very real chance Tyson would stop him. We'll never know though, of course.