tough to come back and with Marciano's style you need to really be fit. He may have gotten into enough shape to beat INGO but then what next and from his own assessment he was not happy with where he was at....I think he made a good choice, very smart man Marciano, He was fair in what he said about Ali at the time and i.m sure he would have been fair had he lived to see Ali later on. thing is styles would make great fight between Ali and Marciano as we seen with Frazier and Ali but this one (Marciano-Ali) may have been a bit more brutal...either way a good match-up
Marciano and Ali gained a great deal of respect for eachother in their sparring in 1969. I know Ali walked away very respectful of the Rock's fighting abilities and especially his strength and power. I think Ali-Marciano would be a trilogy affair, similar to what he did with Frazier. Marciano hit harder than Frazier, but Frazier's left hook was more suited to land more against Ali than Marciano's own left hook. It'd be absolutely brutal for both fighters, though.