The underhook is a fundamental Jiujitsu tactic used frequently from a wide range of grappling positions.
The underhook involves hooking and securing your opponent's shoulder with your own arm under your opponent's armpit. The shoulder clamp is a form of underhook, which involves clasping both of your hands in a gable grip and securing the shoulder between your forearms.
Underhooks can be used from nearly every position: standing, the guard top and bottom, side control, mount, and back control. Competition for the underhook often plays a huge role when grappling in the half-guard.
An underhook can provide an excellent grip for controlling and directing movement, and for entering into submission moves. Check out a couple of techniques below:
• from under guard, underhook shoulder clamp to arm lock
• from under half-guard, underhook to shoulder clamp to sweep
When we work on the same tactic from a variety of positions, we start to see patterns and similarities that can really accelerate our progress and open up creativity in each moment.