* Summary:
This Ashi waza (Foot / leg techniques) closely resembles the Osoto-gari (Large outer reap) Waza.

* Features of this Waza:
Like the Osoto-gari (Large outer reap), this Osoto-otoshi (Large outer drop) Waza destabilizes the opponent in the backward direction, with Tori (Player executing technique) using his leg as the fulcrum to throw Uke (Player receiving opponent's attack) onto his back.

* Waza details:
Tori (Player executing technique) destabilizes Uke (Player receiving opponent's attack) in the same manner as in the Osoto-gari (Large outer reap) Waza. In order to facilitate a forward pull, Tori (Player executing technique) Tsurite (Lifting hand) grasps Uke (Player receiving opponent's attack) collarbone area, and his Hiki-te (Pulling hand) grasps Uke (Player receiving opponent's attack) below the elbow.

Tori (Player executing technique) pulls Uke (Player receiving opponent's attack) forward on the Hiki-te (Pulling hand) side, and moves his body inward and advances his Support leg to Uke (Player receiving opponent's attack) Tsurite (Lifting hand) side.

At the same time, Tori (Player executing technique) bends the knee of his Tsurite (Lifting hand) side leg to prepare for wrapping it around behind Uke (Player receiving opponent's attack).

Up to this point, this Osoto-otoshi (Large outer drop) Waza closely resembles the Osoto-gari (Large outer reap) and the Osoto-guruma (Large outer wheel).

But whereas the Osoto-gari (Large outer reap) reaps one leg, and the Osoto-guruma (Large outer wheel) reaps both legs, this Osoto-otoshi (Large outer drop) Waza requires that Tori (Player executing technique) slide the calf of his leg across the back of Uke (Player receiving opponent's attack) thigh and then down to the floor, using that leg as a fulcrum to throw Uke (Player receiving opponent's attack) straight downward onto his back.

Moreover, the Osoto-guruma (Large outer wheel) throw features a rotational motion, whereas in the Osoto-otoshi (Large outer drop), Tori (Player executing technique) stands with both feet on the floor in a stable posture while destabilizing Uke (Player receiving opponent's attack) in the backward direction, and then uses his upper body strength to drop Uke (Player receiving opponent's attack) to the floor.

Although it can be difficult to differentiate between these 3 Waza in actual competition, they can be identified by the manner in which the leg is used, and by the manner in which Uke (Player receiving opponent's attack) falls.