Who ya got?
You know the guy is going to have to go all out in this situation. The "don't ever hit a girl" rule doesn't hold up in the boundaries of the ring. If he loses, he will never live it down. He'd probably have to drop out of the Marines from the embarrassment.
Taking on a girl in fighting-type competitions is always kind of uncomfortable. Maybe that's sexist for me to say, but it's true (not saying they don't belong there because they're women, just stating feelings is all). I remember back in high school, a few of the lightweights on my wrestling team had to take on girls and they never went easy. I mean, no brutal slams or anything; just pinned 'em as fast as possible to end the awkwardness.