Marciano beat Ali. Didnt you all see it? Ali kept knocking off rockys wig. Rocky got angry and said if you do that again i will kill you. Ali said even way after he gave up boxing Rocky had an unbelievable punch. Ali was great but not the Greatest as he would say to all. My case.....Apart from Frazier and Forman who did Ali beat who we would consider a great fighter thus putting Ali as the greatest? if you look at the lower divisions many fighters could claim to be the best ever after having brawls and fighting worthy contenders. What about the 80s light/middleweight and middleweight? Duran, Leonard,Hagler and a few other fighter in this weight that were awesome in their own right. These fighter fought each other more than once and had skill, endurance,technical skill and hearts of gold . They alway fought the best. Ali fought a few bums, actually quite a few. just my opinion sorry. To name a few more worthy contenders, Joe louis fought everyone in his time and ruled for years, Tyson youngest heavyweight knocked down most and he was half the size, Azuma Nelson, tiny but amazing skill and unbeatable, oscar dela hoya,champion at many different weights and fought all the best fighters(no bums) etc etc etc. We had some good British fighters also.