Nikajō with foot trapping – Technique 9 of the Budō Manual (1938)

Nikajō designates the second principle and corresponds to the second kajō, which, in Daitō-ryū Aikijūjutsu, are technical classification categories. This particular principle is known as Nikkyō in most modern Aikidō federations.

This is a translation from the description of the technique from the Budō manual :
"Tori: Attack your opponent's face and ribs as explained in the fifth sequence.
Uke: Try to block the strike with your right arm.
Tori: Make a wide rotation and use your right hand to press down on your opponent's wrist. Return to the axis of their arm while placing a reverse grip on their wrist, which you bring against your chest. Then grab their forearm with your left hand and turn forcefully to gain control with a lock (21, 22 and 23). Take a step back and force them to lie down on the ground. Hold their right arm with both hands (24). This is immobilisation no. 2."

These photographs are particularly interesting because they show O'Sensei stepping on Uke's foot while performing the lock (Figures 22-23) and also because this technique is initiated by Tori, who strikes first, and uses Uke's defensive response to perform the technique.