Masakazu Imanari is a Japanese MMA fighter and grappler who is renowned for his leglock skills. His nickname “Ashikan Judan” means “The Great Master of Leg Submission”, and the “Imanari Roll” and “Imanari Choke” are moves named after this leg lock master.
In the video below Masakazu Imanari shows off the leg lock skills that earned him accolades as a grappler: