If one is a true boxing fan and studies the history of the sport, then he should know that the boxing media back in Rocky's era didn't give him much chance against Joe Louis, Walcott or Charles and we all saw what happened when the Rock connected with their chins. Most fans today say that Ali or Tyson would have an easy job with the G.O.A.T. and only undefeated heavyweight champ in history but I say that Rocky would just improve his record to 51-0 if he fought against Ali and Tyson.

No heavyweight under 6'3 beats the Rock, that's a plain fact.

Rocky Marciano

Many would consider Marciano undefeated, therefore , unbeatable, but most of his wins were against older fighters, once retired and coming back or no more than 6' and 195 pounds at best. A prime 220 pound Tyson, a prime Tyson beats Marciano everytime. IMO.

Tyson by vicious knockout. Marciano gives a good fight until he is overwhelmed by too much speed and power.

Tyson by knockout in 4.

tyson 5th round body blow upper cut.