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“The Serbian Foot Lock” in a competition situation

The original video showing how to execute the technique is here: http://www.bjjeasteurope.com/2012/03/bjj-eastern-europe-techniques-serbian.html

This is the my team mate Zarko Vasilijevic tapping me out with a “Serbian foot lock” last year during one of our closed door (inter club) tournaments. You can see the technique is the most powerful when he stretches his legs and rolls on his stomach, fulling extending and twisting the leg.