Underhook Sweep Defender

Defending the underhook sweep from butterfly guard top is fundamentally a battle for the upper body and your own weight distribution. The seated attacker wants a deep underhook, your weight loaded forward onto their butterfly hook, and your posture broken to one side; deny any one of those and the elevation collapses. The highest-percentage defense is prevention - winning the underhook or establishing a two-on-one before they reach depth, while keeping your hips back and your base wide so there is no weight on the hook to lift. Once the underhook is established you must react immediately with a whizzer, flatten them with a crossface, and kill the hook by pinching your knee in, all without diving forward into the very momentum the sweep needs. Reading the setup early and refusing to feed the hook turns their best reversal into a stalled, passable scramble.

Opponent’s Starting Position: Butterfly Guard (Bottom)

How to Recognize This Attack

How do you know when someone is attempting Underhook Sweep?

• The attacker’s inside arm digs deep under your arm and reaches toward your far hip or lat, not just your ribs
• The attacker comes off their back onto their underhook-side hip, angling their shoulders toward you
• You feel an active butterfly hook lift under your thigh as they pull you forward to load your weight
• The attacker’s far hand grips your wrist or sleeve, or hugs across your back, to remove your far-side post
• Their head drives tight to your chest on the underhook side, blocking your crossface attempts

Key Defensive Principles

What are the key principles for defending Underhook Sweep?

• Win the underhook battle first - fight for your own underhook or a two-on-one before the opponent reaches depth
• Keep your weight off their butterfly hook by basing wide with your hips back, so there is nothing loaded to elevate
• Whizzer an established underhook to neutralize the lift, but flatten laterally rather than diving forward
• Maintain a crossface to drive their head away, killing the angle their torso rotation requires
• Kill or pin the hook by pinching your knee in or pushing the leg down to remove the elevator
• Never reach your far arm behind you to post - keep your arms in front to deny the kimura and the back

Defensive Options

What can you do to defend against Underhook Sweep?

1. Contest the underhook early - pummel for your own underhook or establish a two-on-one

• When to use: Immediately as the attacker reaches under your arm, before they secure depth to your far hip
• Targets: Flattened Half Guard
• If successful: You deny their primary control, flatten them to their back, and begin your passing sequence from a dominant position
• Risk: If you contest too late after the underhook is already deep, they may secure the angle and load the hook

2. Whizzer the underhook arm and drive a crossface to flatten them, keeping hips back

• When to use: Once the opponent has secured a deep underhook and you can no longer prevent it
• Targets: Flattened Half Guard
• If successful: You neutralize the lifting power of the underhook, flatten their shoulders, and can begin passing or threaten a kimura
• Risk: Over-driving the whizzer forward feeds the dogfight back take, so you must flatten laterally rather than diving in

3. Kill the butterfly hook by pinching your knee in or pushing the leg down, hips back

• When to use: As you feel them trying to load your weight onto the hook before the elevation begins
• Targets: Half Guard
• If successful: There is no active elevator, the sweep stalls, and you can pressure forward into a passing position
• Risk: Reaching down for the leg can break your posture and expose your head if you over-commit

4. Keep your weight off the hook and base wide with a tall, hips-back posture

• When to use: Throughout the exchange, especially the moment you feel them pulling you forward to load
• Targets: Half Guard
• If successful: They cannot load and elevate, the sweep never gets started, and the position stays neutral or passable
• Risk: Staying too tall and static invites the arm drag to the back, so combine base with active hand-fighting

Best-Case Outcomes for Defender

What is the best outcome when defending Underhook Sweep?

→ Flattened Half Guard

Whizzer the underhook arm, drive a crossface across their jaw, and flatten their shoulders to the mat while keeping your hips back. Once they are flat, the underhook loses all lifting leverage; settle your weight and begin your half-guard passing sequence.

→ Half Guard

Kill the active hook by pinching your knee in and keep your base wide with your hips back so the elevation fails. As the sweep stalls and they retain a half-guard leg, consolidate top half guard with a crossface and start working knee-slice or smash pressure.

Common Defensive Mistakes

What mistakes should you avoid when defending Underhook Sweep?

1. Letting the opponent secure a deep underhook unopposed

• Consequence: Their upper-body control becomes the launchpad for sweeps and back takes, and all later defenses become far harder
• Correction: Contest the underhook from the moment you engage - pummel for your own underhook or a two-on-one and drive your shoulder into their chest

2. Loading your weight forward onto their butterfly hook

• Consequence: You hand the attacker the exact elevation the sweep needs, making the reversal nearly automatic
• Correction: Keep your weight back and off the hook, basing wide so there is nothing loaded for them to lift

3. Posting your far arm back behind you when you feel the tip

• Consequence: The exposed arm becomes an easy kimura target and provides almost no real base to stop the sweep
• Correction: Post forward or wide with your hand near their head, and recover base with your legs rather than reaching backward

4. Whizzering but driving forward too aggressively

• Consequence: Your forward momentum feeds the dogfight back take as they come up underneath you
• Correction: Whizzer with your hips back and flatten them laterally; do not dive your weight forward into the whizzer

5. Staying tall and static to avoid the sweep

• Consequence: A passive upright posture invites the arm drag to the back even if it stops the elevation
• Correction: Combine a low, based posture with active hand-fighting to deny both the underhook and the arm drag at once

Training Progressions

How do you train defense against Underhook Sweep?

Phase 1: Underhook Denial - Winning the underhook or two-on-one from butterfly top Partner works to establish the underhook from seated butterfly while you focus exclusively on pummeling for your own underhook or a two-on-one and driving shoulder pressure. No passing yet - purely win the upper-body control battle and keep them from turning onto their hip. Drill 30-second rounds with reset when either player wins the grip.

Phase 2: Hook and Weight Management - Keeping weight off the hook, basing wide, and killing the hook Partner establishes an underhook and attempts to load your weight onto the hook. Practice keeping your hips back, basing wide, and killing the hook by pinching your knee in or pushing the leg down. Partner adds moderate resistance and tries to elevate; focus on never feeding weight to the lifting leg. Drill both sides.

Phase 3: Whizzer and Counter Chains - Whizzering without over-driving and defending the branches Partner chains the underhook sweep into the arm drag when you stay tall and into the dogfight back take when you over-drive the whizzer. Practice whizzering with hips back, flattening laterally, and recognizing each chain so you can re-square and re-flatten. Use progressive resistance from 50% to full.

Phase 4: Live Positional Defense - Passing the seated butterfly while defending the underhook sweep system Positional sparring from butterfly top with the goal of passing while defending the underhook sweep. Start standing or in combat base against a seated partner; score for passes, partner scores for sweeps or back takes. Develop the ability to keep weight off the hook and stay offensive rather than purely reactive.