It goes back to the usual, women and men are different (duh! :-) ) and men have greater upper body strength than women so women are at a disadvantage trying the match up with men in rounds of pugile sticks. Plus the male Marine charged at her and she just stood there and got knocked on her keister. Maybe if she had of met his charge with a charge of her own, she might have stood a chance, but I didn’t see any aggression in her, another obvious disadvantage.
Problem is worse than that. She had a couple of seconds to react and did nothing. She could have knelt down and landed one in the cajones when he went up high. Instead she acted like a deer in the headlights.
Fighting is about reaction time. It was clear she didn’t have any.