The **Rear-Naked Choke (RNC)**—known in Portuguese as the *Mata Leão* ("Lion Killer")—is a blood choke applied from an opponent's back. It is widely considered the single most effective and high-percentage submission hold in the history of mixed martial arts and Brazilian Jiu-Jitsu.

## Mechanics & Execution

The RNC is a blood choke, meaning it restricts the flow of oxygenated blood to the brain by compressing the carotid arteries on either side of the neck. When applied correctly, it can cause an opponent to lose consciousness in less than 10 seconds.

**Step-by-step execution:**

1. **Establish Back Control:** Secure hooks (inserting feet inside the opponent's thighs) and a seatbelt grip around the opponent's torso.
2. **Wrap the Throat:** Slide the choking arm around the opponent's neck, aligning the opponent's trachea with your elbow crease to protect it from crushing pressure while focusing compression on the sides of the neck.
3. **Clasp the Bicep:** Clasp your choking hand onto the bicep of your non-choking arm.
4. **Hide the Hand:** Tuck your non-choking hand behind the opponent's head to prevent them from grabbing your fingers.
5. **Squeeze and Squeeze:** Expand your chest, pull your elbows back, and squeeze to finish the choke.

Why "Naked"?

The term "naked" refers to the fact that the choke is applied without needing the opponent's clothing or gi jacket to complete the submission (unlike many traditional Judo or Jiu-Jitsu collar chokes). This makes it highly versatile for no-gi grappling and modern MMA.

## Defense Against the RNC

Once the choke is locked in fully, escape is virtually impossible, and tapping is required. Successful defense must be done early:

- **Fight the Hands:** Keep chin tucked and immediately grab the opponent's choking hand/wrist to pull it down (peeling the hand).
- **Protect the Neck:** Avoid letting the opponent link their hands.
- **Clear the Hooks:** Fight the opponent's leg hooks and slide your back flat against the canvas to escape the back control position.