Marciano has 0 kos over world class opposition inside three rounds (excluding the Walcott rematch) but he's going to do it against, someone bigger, faster, and better defensively? OK.
Which fights? He was still (for the most part) in position to throw another punch if he missed. Unlike Frazier who would over-swing with the left and leave himself completely open for counters. Pay attention to the way they throw the Gazelle left-hook.
Well none of those fighters were taking the fight to Marciano either, The way I look at it, Frazier having better defense is irrelevant because most of the fight is going to be taking place on the inside where Marciano's shorter arms are gonna have a major advantage, Then you have the fact that Marciano hits hard with both hands and that he has a higher work rate than anyone Frazier ever fought. Frazier being a bit bigger is irrelevant because Marciano was knocking guys who were bigger than him in basically every fight he was in and he was known for hitting people on the arms to prevent them from defending themselves. Marciano has a good chin as well. I could see him taking a lot of punishment from Frazier. I never said that this fight would be a cakewalk. I just don't picture it lasting very long considering the traits of both fighters is overwhelming their opponent with volume. I could easily see Frazier win inside the first 3 as well.