P.S. - Years ago I got into a scrape with a guy who was a black belt, and also an experienced dirty fighter. I wasn't. First thing he did was kick me square in the groin with a solid mae geri keage (front snap kick). It hurt some at first, but the funny thing was I was so pumped up after getting jumped by this guy, I didn't really feel it until after the fight was over... and for a few days after.

P.S.S. - Incidentally, that was also the day when I discovered that most of the stuff I was training in class didn't work in a real fight against an aggressive, committed, resisting opponent. In retrospect, it would have been nice if I didn't have to get kicked in the sack to learn that lesson... but no pain, no gain I suppose. :)