[Martial Arts] Unbalance an opponent?

[MrFix]

A lot of media, and seemingly a lot of police techniques include strikes that 'unbalance' or relax opponent via pain or distraction, opening him up for a different, more risky maneuver. Stuff like:

Striking at stomach or groin to distract with pain stimuli and then while the enemy is grabbing either, do a face punch or any other strike

Before or after grapple, kicking opponent's legs from under him so they lose center of gravity, fully relying on your hold to stay upright, and be unable to defend themselves

Pulling garrotted enemy into your back to make defense harder/impossible etc.

I want to say Shock penalty is perfect to emulate these, but of course Shock doesn't apply to active defenses. Is there any RULES LEGAL way to do these things?