Fuck that just walk away man. What are you in 8th grade? This isn't Mortal Kombat?
Dude, one of my good friends in undergrad took a guy up on his challenge for a fight, like what you are saying... My buddy shows up, and in LESS than a minute, the guy he was fighting pulls out a 9 iron and gives it to him smack in the face. Next thing my boy remembers is waking up in a hospital with a fractured cheek bone and a whole bunch of other problems that left him there for a few WEEKS.
Yes it sounds really fucking awesome to redeem yourself and be all macho and beat some ass, but honestly fighting really should be a last resort in a life and death situation! I'm not saying be a bitch and get pushed around all the time, but don't walk into an organized street fight for the sake of fighting! Its not like in the movies man. You are already saying you're gonna fight dirty, what makes you think this guy isn't going to do the same thing, how do you know he wont fucking rip your balls off! There are no rules man, no refee, and no auditorium of fans cheering for you! Be smart dude!