As for Rocky Marciano? Don't take my word ... I'm nobody, but this is what the great and legendary handler and fight trainer (who is more than 80 years old, and still training fighters .. and trained 18 world champions) Lou Duva ... had to say about it!
LOU DUVA --- I say Rocky Marciano was the greatest heavyweight of them ALL. I can only go by one thing; no one ever beat him!
Rocky ... had the perfect style. He made this style to beat any fighter at all, and he had the tools. Rocky had Charley Goldman, a very great trainer, and Rocky was a great pupil. It was a combination that would be hard to beat, and it never was beaten.
I'm one of the old timers; I never watched a fighter as much as I watched the trainer. You've got to show a fighter and tell him why? And that's the main reason that Goldman was a great trainer. He explained everything to Rocky and told him why? he should do it!
Rocky was relentless. He'd bang your body, arms, head all over (he could hurt you no matter where he hit you!).
He would charge an opponent (he bulled them!) and keep going after him throwing punches. He NEVER backed off, and ALWAYS went forward. He was the best; not because of style ... but the tenacious .. and his heart.
In fact, I adopted Rocky's motto myself, which was don't ever hold back, just go right in there and "keep punching." How could a guy put togather an offense of his own if he had to keep blocking punches?
I'll never forget when his nose was split wide open ... by Ezzard Charles .. and several other times when his eyes were busted up ... and cut so bad .. he could not see. Rocky just kept on going forward and punching relentlessly until he knocked them all out.
He was one of a kind.
(source: Lou Duva)
JCC