I think Willard got to the top of the division due to size, stamina, decent chin, decent one punch power, ok left jab at times, luck getting to fight Johnson in a 45 rounder instead of 15 rounds I just don't see any skill defense guile or speed in Willard
It's a big size difference for sure, but I would not rule Marciano out. look at the weights of some guys who did beat Carnera. Jim Maloney - 195 Jack Sharkey -202 Larry Gains -200 Stanley Pareda - 201 Joe Louis - 196 Leroy Haynes - 197. All bigger than Marciano but not incomparably so, and they were all much smaller than Carnera. And there is only one guy on there that I'd take to beat Rocky, so I'd say he more than a decent chance.
One of the worst Hw's of all time vs an overatted Hw but who had actual skill and could punch?Marciano is the clear favored here,anyone can this by just looking how bad Carnera actual was and some of his losses.