We start in hidari gyakuhanmi katatedori.

You need to extend Uke‘s left arm outward so that you can move into uchikaiten (go under his arm). Of course the extension is designed to take Uke slightly off balance, but not so much so that he has to step or readjust. Also, a straight-right-armed atemi to his face helps. Since this is sankyo followed by ikkyo omote, you don’t want to go behind Uke. So, the extension is more sideways and not that much back. This is a sliding motion with his arm extended to about eye level. Twist the hips to protect your groin from a snap kick.

Because you are doing atemi to his face, you have one weapon at the ready for when you enter under his arm. Enter and kaiten but still be beside him. Do not go back behind him like you would for kaitennage or sankyo ura.

The neat thing comes next. If Uke has a tight grip (which is good), then the temporary sankyo will be dramatic. Hold on to his wrist with your right hand (like holding a sword), and extend your fingers and flatten your left palm so it is facing the ground, but slowly rotate it so the fingers want to point toward Uke‘s head – you are using your tegatana against his pinky finger. This is effectively a fancy sankyo (normally, his fingers would be gripped).

Your left hand, if aiming toward Uke‘s head, can dart out and go under his arm and grasp his elbow using the Y of your left hand. Notice how your right hand is grabbing his right wrist still? This is a good grip for the final ikkyo – there is no need to change the grip. Relax the grip though because we don’t grab the wrist in normal ikkyo anyway.

Extend Uke out sideways, not to his front or rear, but sideways. If you are doing proper ikkyo, you will end up in the same ikkyo omote as normal – with his elbow lower than his wrist, and his wrist on your thigh.