Great answers guys! I see BHop edging this since he has all the tools to win a fight, however Kalambay's footwork and slick style may cause some difficulties for him. I've recently watched Kalambay vs Doug DeWitt (the fight before Kalambay's KO loss to Nunn). What an underrated fighter he was. So elegant and smooth and perhaps one of the best pure boxers. I need to rewatch his McCallum fights.
Has anyone picked Kalambay yet? I'd probably go with him as he's more proven against opponents with great technical skill. Who did Hopkins beat who even came close to McCallum in terms of technique and ring craft?
Kalambay's had a few votes. Stylistically I'd favour him (those legs combined with that brilliant left hand would force Hopkins to play the aggressor or risk being outscored, and he was not at his best in this role, least of all against a fighter like this I'd wager), although SS's analysis may be the most on point of the thread.
In the circumstances he fought them, no one. Nor did he even face one, with the exception of Roy Jones in their first fight.