Aoki Lock

Last updated: June 14, 2026

What is the Aoki lock?

The Aoki lock belongs to the same family as the straight ankle lock and the heel hook, and it borrows from both. A grappler traps the opponent’s foot the way they would for an ankle lock, then rotates it outward instead of cranking it straight. That rotation is the whole point. It turns a linear attack on the foot into a twisting one that loads the inner side of the ankle and travels up into the knee.

The submission is named after Shinya Aoki, the Japanese MMA and grappling veteran who made the finish famous. It has since become a common sight in no-gi competition, where opponents often tuck their heel away to deny a clean heel hook. The Aoki lock answers that defense. A competitor keeps the ankle-lock grip, exposes the heel through rotation, and produces heel-hook-style breaking pressure without ever needing the heel fully out.

From the outside, the Aoki lock looks almost identical to a straight ankle lock. The difference is in the angle of the foot. Where a straight ankle lock keeps the foot centered under the arm, the Aoki lock places the heel against the side of the ribs with the toes turned outward.

The finish blends two forces: the linear squeeze of an ankle lock and an outward rotation that turns the heel in and the toes out. Mostly linear pressure keeps the strain on the inner ligaments of the ankle. Once rotation enters, that danger climbs all the way into the knee, where it loads the medial collateral ligament. To a grappler on the wrong end of it, the result feels like ankle lock and heel hook pressure at once.

Most people meet the Aoki lock while trying to tell it apart from the two submissions it sits between. The straight ankle lock is a linear attack that bends the foot back and compresses the Achilles, threatening to break the foot in a straight line. The inside heel hook is a rotational attack that needs the heel exposed and twists it to wreck the knee. The Aoki lock takes the grip of the first and the twisting effect of the second.

	Straight ankle lock	Aoki lock	Inside heel hook
Attack direction	Linear; the foot is bent back	Linear plus outward rotation	Rotational; the heel is twisted
Primary target	Achilles and foot	Inner ankle, carrying into the knee	The knee, through the heel
Foot position	Tucked under the armpit	Off-center on the ribs, toes turned out	Heel exposed and caught
How it breaks	Foot hyperextension and Achilles compression	Twisting the ankle outward	Twisting the heel to torque the knee

That in-between nature is also why its legality gets debated, and the answer depends entirely on the ruleset.

The lock carries Shinya Aoki’s name because he turned it into a signature finish. At Dream 15 in July 2010, Aoki submitted Tatsuya Kawajiri with an ankle lock in the first round to defend his lightweight title, one of several leg-lock finishes that defined his career. Over time, the grappling community attached his name to the rotating, heel-hook-style version of that attack.

The name resurfaced in October 2023, when Mikey Musumeci submitted Aoki himself with the move at ONE Fight Night 15 in Bangkok, tapping the 40-year-old at the 6:55 mark. Musumeci, a five-time IBJJF world champion, has called the position one of his favorites. Aoki reportedly thanked him afterward for using it.

Legality depends on the ruleset and on how the lock is finished. The submission sits on the line between a legal foot lock and an illegal twisting knee attack.

In IBJJF gi competition, heel hooks and knee reaping are banned at every belt level, and a true outward-rotating finish makes the Aoki lock behave like an inside heel hook. Finished with purely linear pressure on the ankle, it can pass as a legal straight foot lock. One IBJJF referee, answering a question about the position, put it plainly: sit straight back and attack the ankle, and it stays legal; rotate the foot outward, and it becomes an illegal heel hook.

No-gi is more permissive. Since the IBJJF’s 2021 rule change, brown and black belts can use heel hooks and reaping in no-gi, and most submission-only and ADCC-style events allow the full leg-lock arsenal.

Frequently Asked Questions

Is the Aoki lock the same as a heel hook?

No. It mimics an inside heel hook’s twisting effect but uses an ankle-lock grip and does not need the heel exposed, which is why it works when an opponent hides the heel.

What does the Aoki lock attack?

Mainly the inner ligaments of the ankle. With more outward rotation, the pressure transfers to the knee and loads the medial collateral ligament, which is what makes it dangerous.

Did Shinya Aoki invent the Aoki lock?

He popularized the rotating ankle-lock finish, and the technique took his name. The underlying ankle-lock mechanics existed before him.

Why is the Aoki lock effective in no-gi?

Modern grapplers hide the heel to defend heel hooks. The Aoki lock produces similar twisting damage from an ankle-lock grip, so it works even when the heel is not exposed.

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Sources

1. ESPN. “Dream 15 Fightcenter: Aoki vs. Kawajiri.” Accessed June 2026.
   https://africa.espn.com/mma/fightcenter/_/id/400252175
2. ProMMAnow. “Dream 15 Live Results and Play-by-Play.” Accessed June 2026.
   https://prommanow.com/2010/07/09/dream-15-live-results-and-play-by-play/
3. Sportskeeda. “ONE Fight Night 15 Results: Musumeci Submits Aoki.” Accessed June 2026.
   https://www.sportskeeda.com/mma/news-one-fight-night-15-results-mikey-musumeci-uses-aoki-lock-submit-shinya-aoki-openweight-grappling-war
4. Evolve Daily. “What Is The Aoki Lock?” Accessed June 2026.
   https://evolve-mma.com/blog/what-is-the-aoki-lock/
5. Grapplearts. “The Step by Step Aoki Lock.” Accessed June 2026.
   https://www.grapplearts.com/the-step-by-step-aoki-lock/
6. Jiu Jitsu Legacy. “The Aoki Lock: Beginner’s Guide.” Accessed June 2026.
   https://jiujitsulegacy.com/videos/techniques/the-aoki-lock-beginners-guide/
7. BJJ Fanatics. “Are Leg Locks Legal in BJJ?” Accessed June 2026.
   https://bjjfanatics.com/blogs/news/are-leg-locks-legal-in-bjj
8. FloGrappling. “The New IBJJF Rules For Heel Hooks And Leg Reaping in 2021.” Accessed June 2026.
   https://www.flograppling.com/articles/6856722-the-new-ibjjf-rules-for-heel-hooks-and-leg-reaping-in-2021

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