Ura Nage (裏投) is one of the original 40 throws of Judo as developed by Jigoro Kano.
It is also part of the current 67 Throws of Kodokan Judo.
Tori will respond to the strike by stepping forward and into Uke's armpit to avoid the strike and close distance with Uke.
While stepping forward, Tori will lower their body weight and step one foot past uke's hip and the other foot inwards between uke's legs.
While pressing upwards with hands and hips, Tori will move the foot between uke's leg inward while dropping shoulders towards the mat behind them.