The bane of game systems eternal --- WRESTLING

So in the conclusion of my first SF adventure last night, one of my players used wreslting on a guy they were capturing.  The scene went over fine... he grabbed the guy, another character could then easily strip the guy's rifle away from his hands.<div><br /></div><div>But i was wondering... is there really just no defense against wrestling except going full defense (not attacking and getting impossing a -15% to the attack)?</div><div><br /></div><div>I'm thinking there is not... and that wrestling... with it's special quality of being resolved first before other attacks is meant to be pretty powerful/useful.  Do cause an insignifigant amount of damage but you pretty much pin the guy on a success?</div><div><br /></div><div>I was thinking that somebody with Martial Arts might be able to oppose the wrestling attempt as a house rule.  Bad idea?</div>