Gee, FF, I guess that depends:.............are you a fighter or a martial artist!

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Man, I would just go in there and box them straight the heck up! What level of contact are we talking about here Make sure they are aware of little trapping and unbalancing things you do are valid techniques in your style, cause they certainly won't recognize it as anything but brawling.
I mean, just hit them hard!
Of course, I might only spar with them contingent that in a couple of weeks, they come to your school and spar with yall according to YOUR rules!