Mike Tyson by much more of an amount than most classic posters might think for my money. Both come forward fighters who walked onto shots. Tyson has much better defence, but Marciano had an underrated defensive skillset - quite simply, Mike took bombs from much bigger fighters who hit harder, whilst Marciano took shots from sharp hitters, but where Mike is effectively, fighting a completely different weightclass, the benefit of the doubt should lie with Mike. Mike's chin is severely underrated and whilst stopped, you didn't get Mike out of there with one punch. It was moreso that his intangibles around surviving those deep water moments weren't up there with the very elite, but it wasn't due to his chin. I actually think Mike takes a single flush shot better than Ali, but doesn't have Ali's indomitable will and durability to the body. Rocco demonstrated an ability to get up off the floor and fight back that Mike never did, but there's a world of difference between the average size and the power of the fighters that these two met. Rocco has an elite cruiserweight chin but he just wasn't tested at the level and size of general fighter that Mike was.
Demonstrably Mike took a better single shot than Rocky did - directly speaking, I do not see Mike going down from the Walcott and Moore punches that dropped Rocky. Maintaining your resolve to win whilst taking lots of hurtful shots that aren’t quite hard enough to actually put you down is another discussion again - but relativity still comes into it given that Tyson faced bigger punchers than Rocky did.
Marciano was decked by Light Heavyweights. Tyson on other hand took single hard punches from 230 pound big hitters like Ruddock without ever being wobbled. So its Tyson clearly for me.
Gotta be Tyson. If Rocky had faced guys like Douglas, Ruddock, Bruno, Holyfield, Lewis then we'd have had a better idea how good his chin was. Still a great fighter.
Better chin?...Marciano went down 2 times in his career...and came back to win! Tyson goes down...the fights over...you've got him! Tyson never came from behind to win...Tyson never had the S**T beat out of him...and then come back to win the fight...Tyson never got up off the deck...and then won the fight! Marciano is ranked...right now...at #4 on the Heavyweight list. Tyson is usually near...or at the bottom. Why? Because he's lacking in the "heart" department! If Tyson can't bully his opponent....the fights over! Talk about "Revisionist" history..."Iron" Mike...not after Buster Douglas....
Tyson did have the **** beat out of him. By a higher calibre of fighter than Rocky ever fought at or near their peak. And it took beating the **** out if Tyson to finally take him out. What do you think Rocky would have done after taking round after round of beating against Lewis? Let’s have a guess. Came back and knocked Lennox out with one right handed with his nose and ears hanging off and both his eyes closed.
Hard to be sure really. We never saw Marciano stopped, but Tyson fought a lot more punchers. Of course Marciano is going to go down if James Douglas is stuffing him for round after round, he is only human at the end of the day. I don't really like grading fighters chins based on who dropped them, because I don't think it is much of a measure of where their breaking point is. However Tysons chin seemed to take a ton of punishment even to budge it, so I woudl be inclined to think that his chin was the better.
Tyson withstood a beatdown from a 234 lb Douglas, for 10 rounds, who was in a bad mood. That alone qualifies him to be superior to anything Marciano withstood. Then there's all the later beatdowns he got after prison where it still took forever to get rid of him.
Rocky Marciano was probably easier to knock off his feet than Mike Tyson was, due to his smaller size. Even then, he was only knocked down twice in his career. I agree that Mike fought the larger fighters, and the harder punchers overall. I am not at all sure that means that Mike could take a better shot to the chin. It may, but I really do not know for sure. If backed into a corner, I would probably guess that Mike had the better chin, but not by very much.
Tyson by a mile. 1986 Mike Spinks was a better fighter than anyone Marciano faced in the form that they were. This isn't even a discussion.
It’s true that KDs suffered obviously aren’t necessarily all she wrote on a fighter’s chin. Patterson was KD’d a lot - but if one overweights that particular stat, I believe they would be getting a false read on the true quality of Floyd’s chin - which obviously wasn’t iron but I certainly wouldn’t call it glass either. There would be likely many fighters who suffered much less KDs than Floyd did but who were actually stopped/KO’d more than Floyd - with the further qualification that Floyd only didn’t see the distance against two reputable ATG punchers and Muhammad Ali in his 5 (?) KO/Stoppage losses. Suffice to say, old timer Joe Grim got bounced more times than anyone could count - but he kept getting back up most of the time - a form of resilience in itself - recuperative powers being a legitimately interpreted component of a good-great chin. I guess also, even if a fighter displayed a reliably sufficient chin to stand up to the level of power he actually faced (including surviving KDs), it might be fair to assume that it is less likely that he would cope as well against even greater punchers. He might hold up but that would be assuming an even greater and more exceptional chin (= less likely) than we have proof of - therefore, it is naturally less likely though still possible. Mike took harder punches so there is no assumption there - there is proof - and the chin he upheld in the face of single shot power was of such more rare and exceptional quality as to not be so easily assumed, if projected for at all.