For the answer to that you would have to factor in the quality of his opponents ,and their respective ages.Then you can arrive at your own conclusions.
Damn Chock forgot about Norris all these years arguing and there is proof positive. Norris who wasnt as strong or good defensively and actually shorter then Marciano was able to beat a decent amount of contenders in this modern era. Strange how that just goes against the narrative.
Well his resume ain't exactly a murderer's row. Louis was a shot fighter, if Louis had been the same age he busts Rocky's face up badly . A younger Charles beats him, Old guys like Moore and Walcott dropped him. Rocky had some tremendous attributes, determination, toughness , and his conditioning was second to none. But against the prime fighters mentioned I don't think he survives. He's just too small. His reach was 69 inches, that's two inches more than Roberto Duran's.
I don’t think either beat Layne or Lastarza. There is a sick hatred for Marciano on this board. But it’s telling when they’re only argument is he’s short with a small reach. They also use proven false arguments like his defense was poor or he had bad balance all the time (as opposed to when he first started boxing). There is no argument that he can’t reasonably compete with the best as he did in his time. When looking at defense, style, power in both hands, chin, stamina. He would compete in any era. When you have a list of fighters whom were less skilled then Marciano but of the same height and similar reach with worse styles that were able to reach top levels it just astounds me that Marciano is somehow dismissed from competition by some (more through the years). to answer the ops question he beats most has trouble with the best of the best boxer punchers. Like Lewis, Liston. I only see one brawler type in Foreman winning over him. The better boxers like Ali and Wlad and Usyk are toss ups. 12 founders id favor them slightly (not all)15 rounds Marciano takes a few. Marciano also takes care of the likes of Holy Frazier and Dempsey. He controlled tempo and had better defense then all of them while having the advantage of having more power in both fists. The only people I see Marciano straight up losing to would be Lewis Liston Tyson and Foreman. Even then he has a chance against them he was that good. I don’t think the likes of Rahman Quarry Norton McCall and other second raters (not an insult but they were) etc were on his level.
Who knows I’ve seen Marciano listed at 67 and 68 heard people say 69 too. Boxrec has it listed at 70 for Norris wouldn’t doubt a few discrepancies
I get it that his era might not have been the strongest, but he was fighting the best contenders available, and weak eras are ten a penny. I think that we have to ask why no other lineal champion in history was able to match his unbeaten record. I also think that we have to conclude, that he was an exceptionally hard fighter to beat.
Norris was 5 10 and a half and fought anywhere from 215 to 225 at heavyweight. Around 30 pounds heavier than Marciano. Who did Norris beat at heavyweight? A drug addled Greg Page? Jesse Ferguson, Renaldo Snipes. He was knocked out by Nate Miller, Bert Cooper, Vitali, and his blow out to Tyson was ruled a no contest ,he lost a UD to the nut cast Golota and one to Henry Akinwande. Hardly ,,,proof positive .that a 188 pound heavyweight could beat a majority of great heavyweights
Put it this way, if Ray Mancini had fought a 38 year old Alexis Arguello and stopped him , then defended his title by beating a 33 year old Bramble, then stops him in a rematch taking a lot of punishment. He then beats a 37 year old Comacho and retires after beating a 35 year old Greg Haugan. He is then the only lightweight champion in history to retire undefeated at 34 -0 . As the years pass Mancini will be regarded ,,by some,,as the greatest Lightweight in history with his admirers telling us how he'd have beaten Benny Leonard, Henry Armstrong, and Duran. They'd regale us of stories about how his guts , determination and power would carry the day and make up for his skill deficit against those fighters. I mean nobody beat him right?