I had a fight where as we came onto the mat the opponents coach asked if we could have no head contact, so I said OK. I'd never had that request before. At the end of the last round the opponent was tired and effectively just covered up, head tucked in, and was waiting for the bell to ring. I kicked his arms a lot, and down low on his torso under his arms, and to the sides but got no-where. I was frustrated and not thinking, and not being able to go to the head meant he could cover up pretty well. Then I suddenly realised he wouldn't even see a front kick coming he was so covered up, so did one low to his abdomen which bent him over and straight away another to his sternum. At that one he went back and his arms flew out so he was opened up. So I think the key is if it's not working don't get frustrated (as I did) and keep bashing the same thing. Move him around and try different angles, different techniques..