The Rock was a force of nature at 189....he trained DOWN to this weight....AND....he hit like a much bigger man....
Sharkey was good, but Marciano was great. Marciano is in the upper echelon of ATG heavyweights, Sharkey is in a class or two below. :good. If you want to compare Jeffries to Marciano, we have a far closer and more appropriate debate.
I won't disagree. Many posters here have vast knowledge of Marciano but only perfunctory, 'rec-ranger knowledge of Sharkey. Overstatements like "Marciano's chin/stamina/power are in a different universe" are an example.
Sharkey was easily as tough and just as durable probably. But he seems to have really been a crude fighter. Marciano looked crude, only sometimes. But Sharkey was pretty much a pure brawler, and no one said otherwise (from what I've read).