Why didn't you just ask him politely if he was obstructing your view? It's not a way I'd like to talk to someone I don't know. Surely that can't be justified because he disagrees with your friend.
I'll admit I was a few rows behind, but by his reaction afterwards I hardly doubted he wanted an arguement. If he did, a few minutes after it had all calmed down and yous started slagging him off again (something along the lines of him sucking Foran's **** I think) he would have turned around and smacked one of you.
If he was 'chatty' at the game do you really think it would have helped the situation? To be honest if he was, he would have just created another target to be shot down. Actually this thread suggests not everyone had forgotten about the incident.