You can take easily against opponent fight from upward. He does not think that is taken his arm joint because his elbow is bending.
You pull out opponent's right arm with your right hand. Your left hand take his left shoulder.
You take his left shoulder with your left hand. And you catch his body with your both legs, to prevent his escaping.
Your waist turn to the left, your left leg bring to opponent'neck, you take his arm joint by extended your waist.