Round 1: the Vikingr. Gladiators typically had very little armor (usually just a greave and an arm guard), so I suspect they would tire quickly. read more
The gladiators also had the chance to rise after every lost battle, as death was uncommon for a gladiator, unless by mistake or to the death. It is possible that this viking is a very skilled warrior though, but my chances still lie upon the gladiator. read more