I'm looking forward to it as well. To my knowledge it will be the first time in history that a fighter having been an established heavyweight world champ, at one point the longest currently reigning, has moved down two divisions to fight at a lower weight.

(Roy Jones doesnt count as he was never a heavy to begin with)

In fact I can't think of a single fighter in any weight class who spent their career in one division, winning world titles and then moved down to divisions.

Has this ever happened before?