O Soto Gake

O-soto-gake can be executed on an opponent whos legs are too far for an O-soto-gari attack, or after a failed o-soto-gari where the uke has stept backwards.

The tori's heel is used either on the back of the uke's knee as shown in the video, or slightly more through. This causes the ukes leg to buckle and the tori's hannd movements exploit this by forcing backwards with the tsurite and the hikite pulling to tori's chest (much like readying a bow-and-arrow).