None but we're not talking about modern day heavies. And Fitzsimmons as I recall was a little over 150 pounds when he won the title.
Fitzsimmons only hope against LHW Roy, who would be in the ring at 180-185 pounds come fight night with day before weigh ins, would be a lucky punch. I just don't see it being any other way. Even though Jefferies is bigger, his best hope is a lucky punch . They ain't out boxing or out speeding him and they weren't defensive wizards. Roy would land at will. And I'd wager that a 180 pound Roy hits hard enough to take out any 150 something who's 150 something on fight night.
Well if you're going to allow a 30 pound advantage, obviously the decks do become somewhat stacked. But you're knowledge of Fitzsimmons seems a little bit off. He was able to avoid many many punches by leaning back, ask yourself who else has been able to manage this. There's no such thing as a lucky punch.
Yeah but look at the guys he was avoiding punches from. It's safe to say those guys were primitive barroom brawlers and speakeasy bouncers for the most part compared to RJJ. It's kind of like how Kimbo Slice looked very impressive when he was knocking out drunk, fat guys in his backyard and then he started fighting trained professionals and he was inept. It'll kind of be like that. And Jefferies would have a size advantage but RJJ has the speed and skill to overcome it.
You can't look at the guys he was avoiding punches from. Almost all of his career is unfilmed. Its not safe to say anything about them other than contemporary fight reports, which obviously you aren't using.
Judging from what we know of how guys fought back then, it's safe to say that Fitzsimmons wasn't fighting and beating replicas of RJJ. I'd put money of Tyson or Holyfield as amateurs being a lot better than the average 1890s contender.
But you don't know how guys fought back then, because you don't read fight reports from back then. A you certainly can't see fights from back then since Fitz vs Corbett was the first filmed fight. Whilst Fitz has never faced replicas of Jones, Jones has never faced replicas of Fitzsimmons. I'd imagine Tyson as an amateur is better than most heavyweights of any era given how well drilled he was in the peekaboo style, how explosive he was.
To Corbett’s credit, he was a very smart fighter. His boxing IQ is credited across all generations he interacted with from Donovan, to McAuliffe, to Tunney. I think he would realize how hopelessly outmatched he is from the first exchange he has with Roy, and then try to limit the exchanges they have as much as he possibly could and run away. Roy is basically premium Corbett.
Jones gets one look at that thong and ass cheeks and he knows he's got a problem, right here, right now.
Corbett would have full blown PTSD for the rest of his life after what a perceived "inferior" like Roy would do to him.