Lol Rocky Marciano went 49-0 fighting mob controlled fighters and guys who weighed 190 pounds or less. This doesn't equate to him being able to beat any modern sized heavyweight. That is like saying since Floyd Mayweather went 50-0 that means he could become light heavyweight champion of the world.
Finally somebody who gets it. Marciano was a heavyweight for 1950's standards. He wasn't a heavyweight by modern standards. He would be considered a really small cruiserweight by today's standards. Anthony Joshua, Lennox Lewis, Mike Tyson, Vitali or Wladimir Klitschko, George Foreman, Riddick Bowe, David Tua, Razor Ruddock, Ike Ibeabuchi, Ron Lyle, or any other half way decent heavyweight with a good punch would stop Marciano in the first round.
I picked "None Of The Above" before and when I watch Marciano on video I know I made the right choice. Marciano would be outclassed by Andy Ruiz or a 6-5, 235 pound southpaw. Joshua and Fury fought people that were much better than anybody RM ever fought. It is no disgrace to lose to Ruiz and beating a 6-5, 235 pound, undefeated southpaw after getting a big cut early in the fight is impressive.
Rocky Marciano would be knocked out in the first round by all of these guys. You know why again? Because Marciano wasn't a heavyweight. There are weight classes for a reason. Nobody is above them. There is a reason that there are no 5'10 180 pound heavyweights anymore. The reason is that they couldn't compete. So each the guys listed would beat the crap out of Marciano and stop him in the first round.
I disagree. Grannys and Grandpas were Rocky's specialty. I think Rocky would've beaten your old granny by a 14th round TKO (Granny ahead on all scorecards, 9-4).
It’s become a sickness around here. One of the greatest HWs ever being reduced to losing to everyone. Your granny must be one tough woman.
I don’t think anybody is going through a list of great fighters like that without a loss. but Marciano would have good odds against all those boxers imo. Tyson would be his toughest test but I think in the late rounds he could stop him.