Tyson wins. I used to go back and forth on this...based on what Foreman did to Frazier. But Tyson is no Frazier. Foreman would be pushing Tyson back and keeping him off balance and nailing him from distance. Tyson will be in difficulty. The difference however is that Tyson had an ATG chin and he was fast enough to nail Foreman in between that aggression. You have to figure that Tyson would last beyond the 7th round and then it's his territory as Foreman would begin to slow down. Tyson late KO in a thriller.
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I could see a trilogy with this one. But I'll go with Iron Mike. That speed is the big difference maker but at anytime Foreman could catch him with something brutal and that would be that also.
The thing with Forman, is that he could have been a much better than he was if he combined the strenght of his youth, with the skills and cageyness of his older years. If he comes in like a big retard trying to only overpower Tyson by throwing punches from his waist, I think he get KTFO. If he fights intelligently and use his jab and strenght to keep Tyson at bay and hammers him with huge bombs when he stand still, he has a hell of a chance. As I said, I would trust a combinaison of both Foreman to be able to do so, but I'm not sure the actual young Foreman could have done so.