Or Super Middleweight to be competitive or even successful in the current HW scene, which fighter would it be? Inspired by the Super Middle/Jack Johnson thread.
The thing is, which MW or SMW can be competitive with them while staying at 160 or 168? Because this is what Johnson's opponents did. Bulking up with modern methods (steroids) can help a great deal, it makes you bigger and you retain a lot of your speed, even if it is fat, ithelps you take punches (see Foreman and Toney's great durability when fat), etc.
James Toney had more success at heavyweight than Jones. Maybe it was the steroids, maybe it was his style, maybe it was because he just had more fights there. Jones beat Ruiz. Toney beat Holyfield, Ruiz, drew with Rahman, and lost a disputed decision to Peter. So I would have to pick Toney. Based on his resume, and his chin. I've always felt like Ruiz buzzed Jones in the first round of their fight with an insignificant punch. I've seen Toney taste harder shots and still not give the same reaction.
Roy Jones was able to, because of his physical makeup, to rise to the heavyweight divisio, more so than other middles and supermiddles, but he would have only been sucessful against the second tier, inferior heavies, and not the badasses with punches. Outside of the few Ruiz's of the division, Jones would have been brutally ko'd by just about all of the hevyweight stars of the past. If you think Tarver and Johnson were able to hurt him, that's nothing compared to what Louis, Dempsey, Marciano, Frazier, Liston, Ali, Baer, and especially Lewis would have done to him. Why Floyd Patterson would have put him in the hospital with one of his left hooks.
Roy Jones, if he had moved to heavyweight 2 or 3 years before he did would have been able to hold and defend a belt at heavweight. By the time he did move up in weight he was already past his physical prime and only fought Ruiz and moved straight back down. Those 2-3 years before he moved up to fight Ruiz, he was in his comfort zone and making easy defences...that was when he should have moved up and due to his natural athletic gift he would have been a very good heavyweight.