here is what im saying, Frazier hit Ali pretty hard during their trilogy, Foreman got him a few times also in their fight, he was not unhittable, in fact one of his best features was he could take a lot of shots. All im saying is if Frazier could land power shots on Ali, then so could Tyson and believe me NOBODY is getting up when a Mike Tyson left hook lands.
Ali did have great defense, but both Frazier and Foreman landed power shots on him, in fact, Mike Tyson fought more like Frazier than anyone else, both had an unbelievable left hook, tremendous power and both were great in the trenches. I am certain Tyson packed more power into his punches than Frazier did. As far as size goes, all of Tyson's opponents were bigger than him, he is around 5'10". What im saying is its not for certain, one left hook from Mike Tyson and not even Ali would get up.