I'll take Holyfield. Ali hadn't faced anyone worth a damn except Liston at that point. Terrell, Williams , Cooper ,Chuvalo and an old Patterson and Archie Moore. Most were media hyped and others were just flat out too old. Holyfield's resume was pretty impressive fighting everyone in the heavies except for Tyson at that point. I think it would be a close fight but Holyfield wins with combinations Ali just wouldn't have enough power in that jab to keep Holyfield off of him all night.