Junny Lock
The Junny lock — an inside heel-hook variant hit on the opponent's reaping leg while they reap you. Their own entanglement supplies the knee-line control.
Adapted from InGrappling, Junny Lock. System Games did not invent this curriculum.
FamilyLeg LocksLevelAdvancedPerspectiveTopIntentOffensiveSafetyElevatedHubLeg EntanglementsMapView on graph →This technique has elevated risk. Make sure you've covered the prerequisites before attempting.
Manage injuries →Position map Connects to 3 positions across 2 relationshipsOpen in the map →123←Attacked from
The Junny lock is an inside heel hook variant that uses a wrist and forearm wrap configuration rather than the standard palm-to-palm grip. The wrap creates a different lever geometry — the forearm applies rotational force to the knee through a mechanical advantage that differs from the standard inside heel hook finish. The target is the same: medial knee ligament structures, including the MCL and ACL, loaded through internal rotation of the tibia relative to the femur.
The technique sits within the inside heel hook family, but its platform is unlike any other member of it: the Junny lock is an inside heel hook hit without any ashi control of your own. It is a counter — a way of attacking the opponent’s reaping leg while they are reaping you. The knee-line control that an inside heel hook normally demands from cross ashi or 50/50 is supplied here by the opponent themselves: their reap threads their leg around yours, and that self-trapping fixes their tibia on the attackable line. The forearm wrap is what cashes it in, reaching the heel in a relationship where no palm-to-palm grip could be built. It is also found under the name “inverted heel hook variant” in some instructional contexts, though this description is imprecise and can refer to other techniques.
Because the Junny lock targets the same knee structures as the inside heel hook — and does so quickly — it carries the same injury risk profile. The page leads with defence. Understand what is being done before learning to do it.
Elevated RiskJunny Lock is an elevated risk technique. The Junny lock loads the medial knee structures — MCL, ACL, and associated ligaments — through internal tibial rotation. The forearm wrap can apply force rapidly once closed. As with all heel hook variants, the damage signal (pain) can lag behind the structural load — the ligaments are being stretched before acute pain registers. This means the tap window is extremely narrow. Damage can occur within a fraction of a second of the rotation beginning. Serious injury can occur very fast — forearm wrap mechanics can apply rotational force immediately once closed; tap at the first sign of knee rotation load, not at pain.
If you are new to this technique: read this section before anything else. Understanding the danger is part of understanding the technique.
The person applying the technique is responsible for releasing immediately.