Mercer on his best night beats Haye on his for me. You could hit Ray with a bat and he'd keep on keepin' on. Cliche, but it might resemble Morrison v Mercer in that Ray might take a lot of punishment early, maybe up till halfway in this one, but Haye woukd run out of speed, breath and ideas in the second d half. Mercer by KO. Maybe a heavyweight version of Thompson v Haye actually!!
I think Mercer on his best day was too tough for Haye in the long run and would have got the clear and fair decision in a competitive fight.