....you sweep the leg!
For some reason when I read this, all I could picture was this scene from the Karate Kid. (original one of course)
[just before Johnny fights Daniel in the tournament] Kreese: Sweep the leg. [Johnny stares at him in shock] Kreese: Do you have a problem with that? Johnny Lawrence: No, Sensei. Kreese: No mercy.
Kreese: We do not train to be merciful here. Mercy is for the weak. Here, in the streets, in competition: A man confronts you, he is the enemy. An enemy deserves no mercy.