Yeah. There was UFC game on PS2 if i remember right. Some sort of mixed martial arts game in anycase. Actually I think it might of been Pride fighting.
It was fun. Not the most complicated game... or strategy prone game... (I won a tournament my 3 friends and i were in on my first play. They oddly got eliminated before the finals, and have actually played before.)
It was also made by THQ, so i'd expect them to use the same engine.
It basically felt like a wrestling game, with more focus on counters, a ground pounding system and no pins.
Kinda like Fire Pro Wrestling Returns MMA fights.