O-Soto Guruma is similar to O-Soto Gari but in O-Soto-guruma you sweep both legs. Get it right and this is a huge ippon scoring waza!
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Here is a video that shows this technique clearly for you to watch by Efficient Judo.
Techniques that work well in combination with this technique are O-Soto Gari, Sasae-Tsuri-Komi-Ashi and Tani-Otoshi.
This is a double-tap combination. Attack first with an Osoto-Gari. As uke blocks this, release the pressure on the outside leg. Uke, thinking the attack is over will relax a little. Without exiting attack again this time against the far leg.
Use a big circular Sasae to create movement. As uke recovers from this first movement their body weight will sway back. Use this movement to your advantage and follow up with your second attack.
Use Tani-Otoshi to follow up, especially if you really wobble uke with your first attack. Attack strongly with the O-soto and get uke moving backwards. Now finish the throw with the Tani-Otoshi.
Use O-soto Gari or O-soto Gaeshi to counter.
To counter make sure you have control over your partner’s sleeve and head and regain your posture.
Take a step backwards and counter attack with Osoto, pulling uke’s sleeve downwards and steering their upper body.