Alex Crispim was a standout at major Jiu-Jitsu tournaments, as he is now in MMA, fighting in promotions like Strikeforce. Our GMA in California, at the helm of Crispim BJJ Barra Brothers, has as one of his chief specialties the half-guard.
In the series of moves featured in the video below, he demonstrates how to defend the knee in half-guard, slide to an opponent’s back, and finish with one of two options: the choke or the armbar.
Check it out and practice it: