I faced Sir Neville the Dragonslayer in the Spinning Groat Arena on Shan Ronelsin (level 6 - 2 ranger/4 Fighter)
The first bit of oddity was that the doors did not lock like they did in the one other gladiator fight I did. I was able to exit and re-enter the arena while Neville was still hostile inside
Secondly, while he was defeated, he actually died instead of yielding/being subdued. And only granted 2 XP (No prestige/gold or card(?) to go with it)
I'm unsure if it's related to him knocking me below 0 HP during the fight, or my subsequent exit of the arena and re-entrance to fight him in a second round (Not that I deserve a reward for cheesing the fact I could exit/enter for healing)