Sabretooth was always more of wild brute force fighter. He has had a good deal of training, but over all ignores it and prefers to go at his opponent in a more primal manner. Agent Zero turned out to be Maverick, so I didn't mind that he whipped Sabretooth's ass, as I really like Maverick. As far as the story went, Weapon X had given him the ability to shoot a corrosive enzyme blast, as we later found out, this enzyme was specifically engineered to counteract Sabretooth's healing factor. There was nothing Creed could do.