A close one seeing as the characters basically have the same powers and speed, although Gladiator's powers are dependent upon his confidence. I would have to agree with the afore mentioned statement that it's no easy feat to actually break his confidence, the only reason why he did so against Sue was because he saw her as a woman, weak, someone he could demolish easily and it cost him his pride. In Superman, there will be no such estimate. It's proof positive that in other encounters that may have presented diffifuclties that Gladiator retains that confidence and ends with him cleaning house.
On the other hand, based on current Superman, he's well....Superman. This guy has the brains, the brawn, and the heart to endure some of the nastiest punishment available in this universe and the next. I'd bet that Superman is much younger and therefore less experienced in battle compared to Gladiator who seems to of been around the galaxy for quite some time, but Supes has a habit of overcoming odds.
Also, close range, Gladiator is easily Superman's superior in hand to hand combat, and based on the fact that he literally snapped Hyperion's neck, another character that's on Superman's level as far as powers, ect. I'm going for Gladiator in this one.
