This has been done with Frazier and Tyson. How about these two ? Larry Holmes'time at the top of the tree occured when he was between 28 and 36 years of age. If we swapped his career with Ali's at the same age and gave them each other's opponents,imo not much would alter. Holmes would have a split trilogy with Ken Norton,and he would beat Foreman after getting off the canvas. A 1971 Frazier would beat him over the distance but Larry would win the rematches. Quarry would get stopped,and Chuvalo would go the distance. He may have stopped some of Ali's minor opponents quicker,because he tended not to mess around as much as Muhammad. A 28 year old Ali would win the title from an older Ken Norton. There is no way that Alfredo Evangelista would last 15 rounds with an Ali who was six years younger than he was when they actually fought. Also,Ali would have had an easier time with Earnie Shavers than he did in real time. Gerry Cooney would have been seen off by late rounds tko. A 33/34 year old Ali would have had tough fights with Tim Witherspoon And Carl Williams,and finally Deja Vu time when a 36 year old champion loses his title to Michael Spinks on points.
I missed out on mentioning a couple of things. Trevor Berbick would have hung on for the 15 rounds with a 31 year old Ali,but loses by a mile. The Ali of the second Norton fight would have thrashed Leon Spinks. a 35/36 year old Holmes would have still beaten Leon,but it would have taken him longer than his 1981 version did.
Ali goes unbeating and reins until Tyson comes or retires imo. Holmes era was pretty weak and only a prime Tyson would beat a shot Ali at this point. Dont think Holmes would fair as well with Fraizer and Foreman.
