Larry Holmes vs Ezzard Charles
Rarely do I ever pick a fighter pre-1970 to beat Holmes, but in this case I might be willing to make a rare exception.
For whatever reason, Ezzard Charles has managed to impress me on film lately, and frankly I think that his boxing ability, quickness, durability and other attributes may well lead to him taking a close decision in this match. No, I do not consider Charles to be a better fighter than Holmes, and honestly I think Larry fairs better against other all time greats, but head to head Charles has a very good chance here.
Holmes of course, would have the reach, as well as the advantage of being a full sized, natural heavyweight, but I don't think he stops the man who took the very best that Marciano, Walcott and Louis had to offer. Trying to knockout Charles in his prime, was like trying to kill a ****roach. His physical conditioning along with his solid chin and undying work ethic, would have made him a nightmare for almost any all time great really.
I think that while both men were elite boxers with better than average durability, Charles may well have been the faster of the two, as well as a tad more accustomed to fighting in long range fights ( subject to opinion of course.) Addtionally, when I watch footage of him, he seems to be more mult-dimensional when throwing a variety of punches, as opposed to Holmes who relied a bit too heavily on the jab in my opinion. I don't think that Charles dominates Holmes, but squeaking out a close decision, by keeping busier and landing a few more shots per round may well do the trick.