Yes I've once had a fight at a club. I remembered a guy was flirting with my friend's girlfriend, and we tried warning him once but he wouldn't listen. All of a sudden, my friend attacked him. Two of his guys started supporting him, the three of them against my friend. Then I had to step in, and what helped us win the fight was, clearly the flirt and his guys were all drunk. They were bounced out of the club that night after when the bouncers intervened.