Thats some nasty shit. Was strange how he still thought he was in the fight while he was down on the floor! Its similar to a video i've seen of an arabian footballer (soccer player) who got tackled and hit in the head and he kept repeating his fall over and over. Apparently the blow to the head caused this.

Here's the link: http://uk.youtube.com/watch?v=NiVjzSTIPOc