At the moment of writing, Demian Maia and Bernarndo Faria are probably some of the biggest name in Brazilian Jiu-Jitsu, albeit in different disciplines. Mr. Maia has made it big in mixed martial arts, being part of the UFC. On the other hand, Mr. Faria is one of the top heavyweight contenders in GI competition in the world.
The technique we’re looking at is just a simple armbar. You attack it from side control, looking to control, isolate and attack the far-side arm. Remember BJJ day one, the under hook? Yup. That’s what you’ll need. You’d probably have gable gripped the cross-face and under hook to control your opponent when you’d been starting out. Now, you’re looking to use the under hook to attach yourself to your opponent or partner’s arm. Grab under the tricep with a monkey grip. Close your elbow down into your hip. This’ll frame your grip to your body and hip. You’ll use no arm effort to move your opponent. Once you’ve got the grip, post your under-hook shoulder into your opponent’s hip, belly or chest and go into tripod. You could also do the same thing off knee-on-stomach or chest. Use the shoulder or knee as an axis you’ll rotate around. Your under-hook side shoulder or knee is where your weight is centered. Post up onto your cross-under-hook heel and arm. You’ll push off either off the heel or the palm of your hand to rotate. Palm is probably enough. Cross-face side leg goes under your opponent’s armpit. Hook the armpit the way you would with a butterfly hook and put yourself into armbar position. The other leg goes into a cross-face to break your opponent’s ability to stand and posture up.
Bottom line: Grip the tricep. Attach your elbow to your hip. Spin into the armbar.