When is the optimal moment to initiate the butterfly underhook sweep?

The optimal window is when the opponent commits their weight forward - driving into you, posting their hands in, or beginning a pass - because their mass is already loaded toward the sweep direction and onto your hook. Sweeping a settled, based-out opponent whose weight is back will fail regardless of technique, since there is nothing loaded on the hook to elevate.

Why must you load the opponent's weight onto the butterfly hook before lifting?

A based, settled opponent is dead weight you cannot elevate; the hook will simply stall under their immovable mass. Pulling with the underhook shifts their center of gravity forward and onto the hook so the lift actually raises their hip. Loading first is the difference between a hook that elevates a hip and one that just presses against a planted leg.

How deep must the underhook be and why does depth matter for this sweep?

The hand should reach the opponent's far hip or lat. At that depth their torso rotates as a single unit when you elevate, so the upper body topples with the hips. A shallow underhook that stops at the ribs lets them posture out, invites the crossface to neutralize your arm, and leaves their upper body free to counter-rotate against the sweep.

What is the correct direction of force between the hook and your falling body?

Lift the knee toward the ceiling with your instep while falling to your underhook-side shoulder. The hook elevates the hip, the fall creates the rotation, and the underhook drives the torso over the top. Kicking the hook sideways or staying flat produces elevation without rotation, which the opponent simply rides out and re-bases against.

Your opponent whizzers your underhook arm and drives forward - how do you adjust?

Do not fight the whizzer; ride it. Extend your legs and come up to the dogfight to take the back, or hit a single-leg or leg-entanglement entry as they drive forward. If they smash all the way through, retain half guard rather than staying flat. The whizzer only kills the original sweep direction; it actually feeds the back take.

Your opponent posts their far hand and bases wide away from the sweep - what do you do?

Their commitment to one side opens the other. Switch to an arm drag to the back, since their far side is now exposed, or fall the opposite direction for a sweep toward the open side. Forcing the original line against a wide base wastes energy; redirecting to the undefended direction turns their defensive post into your opening.

Underhook Sweep Attacker | BJJ Technique Guide

From butterfly guard bottom, the underhook sweep is the seated player’s most controlling reversal because it removes the opponent’s upper body from the equation before the elevation even begins. Securing a deep underhook to the far hip glues the opponent’s shoulder line to yours so that when you load their weight onto your butterfly hook and fall to your underhook-side shoulder, their entire torso rotates as one unit over the top. Success depends on a strict sequence — underhook depth, an active loaded hook, posture broken to the sweep side, then a simultaneous fall-and-elevate — followed immediately by coming up on top into side control. Executed well it both reverses position and feeds a web of follow-up attacks when the opponent defends.

From Position: Butterfly Guard (Bottom)

Key Attacking Principles

What are the key principles for executing Underhook Sweep?

Secure a deep underhook to the far hip or lat before committing - it controls the upper body so the opponent rotates as a single unit
Load the opponent’s weight onto your butterfly hook before lifting - you cannot elevate a based, dead-weight opponent
Elevate with the hook by lifting the knee toward the ceiling, not by kicking the foot laterally
Sacrifice your own base by falling to the underhook-side shoulder to generate the toppling rotation
Time the sweep to the opponent’s forward weight commitment - when they post in, drive, or attempt to pass
Come up on top immediately - the sweep is incomplete until you have technical-stood-up into side control
Keep your head tight on the underhook side to deny the crossface and to help drive the rotation

Prerequisites

What do you need before attempting Underhook Sweep?

Seated butterfly guard with the sweep-side foot actively hooked inside the opponent’s thigh using the instep
Deep underhook secured on the sweep side, hand reaching the opponent’s far hip or wrapping their lat and back
Far hand controlling the opponent’s wrist, sleeve, or hugging across their back to remove the far-side post
Upright seated posture on the underhook-side hip, off your back, creating the angle needed for elevation
Opponent’s weight loaded forward and onto the hooked-side leg rather than based wide and settled
Head positioned tight on the underhook side to block the crossface and stay connected to the opponent

Execution Steps

How do you execute Underhook Sweep step by step?

Establish deep underhook and far-arm control: From seated butterfly guard, drive your inside arm deep under the opponent’s armpit on your chosen sweep side until your hand reaches their far hip or lat. With your other hand control their far wrist, sleeve, or hug across their back. Keep your head tight on the underhook side and your posture upright so their shoulder line is welded to yours.
Insert and load the butterfly hook: Confirm your same-side foot is hooked actively inside the opponent’s thigh with your instep, not merely resting. Pull their upper body into you with the underhook to shift their weight forward and onto that hook, loading their mass onto your elevating leg before you commit. Dead weight that is based out cannot be elevated, so you must feel their weight on your instep first.
Break their posture and create the angle: Off-balance the opponent toward your underhook side by pulling their shoulder across and down while getting onto your underhook-side hip. This kuzushi removes their ability to post on the sweep side and aligns their center of gravity over your loaded hook, setting the platform for the diagonal toppling motion to come.
Fall to your shoulder and elevate: Commit to the sweep by falling toward your underhook-side shoulder and upper back while simultaneously lifting the opponent’s loaded thigh toward the ceiling with your butterfly hook. The fall generates rotation, the hook generates elevation, and the underhook drives their upper body over the top - all three happening as one explosive, coordinated motion.
Pull the far side and complete the rotation: As you elevate, pull their far arm or wrist across and drive your underhook through to topple them over your shoulder, eliminating their far-side post. Follow their body, keeping the underhook glued, until they roll past their base of support and your hips begin to come over the top of the rotation.
Come up on top into side control: Do not stay on your back. As they roll, post with your free hand and technical-standup, chasing the underhook into a crossface as you settle chest-to-chest in side control. Spread your base wide and drop your hips heavy against theirs to deny any immediate guard recovery or scramble back to neutral.

Possible Outcomes

Result	Position	Probability
Success	Side Control	55%
Failure	Half Guard	25%
Counter	Flattened Half Guard	20%

Opponent Counters

How might your opponent counter Underhook Sweep?

Opponent posts their far hand and far leg wide, basing away from the sweep direction (Effectiveness: Medium) - Your Response: Switch direction using their commitment against them: arm drag to the back as their far side is exposed, or fall the opposite way to sweep toward the open side. A base committed to one direction always opens the other. → Leads to Half Guard
Opponent whizzers (overhooks) your underhook arm and drives forward to flatten you (Effectiveness: High) - Your Response: Do not fight the whizzer; ride it. Extend your legs and come up to the dogfight to take the back, or hit a single-leg or leg-entanglement entry as they drive. If they smash through, retain half guard rather than staying flat. → Leads to Flattened Half Guard
Opponent pushes your head down and backs their hips away to kill the angle (Effectiveness: Medium) - Your Response: Re-pummel the underhook deeper and follow them up to your knees rather than staying seated. As their hips retreat and their near arm becomes exposed, transition to an arm drag to the back. → Leads to Half Guard
Opponent kills your butterfly hook by pinching their knee in and pushing the leg down (Effectiveness: Low) - Your Response: Re-insert that hook or switch the sweep to your other active hook. If the hook is fully dead, thread the leg to trap half guard and re-fight for the same underhook sweep from there. → Leads to Half Guard
Opponent stuffs the underhook and drives a crossface to flatten you to your back (Effectiveness: High) - Your Response: Frame on the hip with your bottom hand, shrimp back to your side, and recover half guard or deep half where the underhook remains effective. Reset the angle and re-attack rather than forcing the original line. → Leads to Flattened Half Guard

Common Attacking Mistakes

What mistakes should you avoid when executing Underhook Sweep?

1. Attempting to lift before loading the opponent’s weight onto the hook

Consequence: You try to elevate dead weight that is based out, the hook stalls, and you expose yourself to the pass
Correction: Pull with the underhook to shift their weight forward onto the hook first; only elevate once you feel their mass settle on your instep

2. Shallow underhook with the hand stopping at the ribs

Consequence: The opponent’s upper body does not rotate with you, they posture out, and the crossface neutralizes your arm
Correction: Drive the underhook to the far hip or lat so their torso turns as one unit the instant you elevate

3. Kicking the hook laterally instead of lifting the knee upward

Consequence: You shove the opponent sideways without elevating their hips, so they simply step over or post and stabilize
Correction: Lift the knee toward the ceiling with your instep, raising their hip off the mat rather than pushing them away from you

4. Staying flat on your back instead of falling to your shoulder

Consequence: You generate no rotational power, the opponent settles their weight back down, and they begin passing
Correction: Commit to falling onto your underhook-side shoulder to create the toppling rotation, then chase the come-up

5. Failing to come up on top after the elevation

Consequence: You tip the opponent over but stay on your back, allowing them to re-base or scramble back on top
Correction: Post your free hand and technical-standup immediately, chasing the underhook into a side-control crossface

6. Losing the butterfly hook mid-sweep

Consequence: The opponent frees their leg, re-bases, and passes to the top before you complete the reversal
Correction: Keep the instep actively lifting until you have rotated past their base and your hips are coming over the top

Training Progressions

How do you train Underhook Sweep (Attacker)?

Phase 1: Static Underhook and Hook Loading - Underhook depth, active hook insertion, and shifting weight onto the hook Partner remains stationary while you drill establishing the deep underhook to the far hip, inserting an active butterfly hook, and pulling their weight forward onto that hook. Focus on feeling the load transfer to your instep before any lift. Drill 10-15 repetitions per side, with the partner giving feedback on underhook depth and weight loading.

Phase 2: Off-Balance and Elevation - Kuzushi to the underhook side and lifting the knee in one motion Partner offers light resistance by basing slightly. Practice breaking their posture to the underhook side, falling to your shoulder, and elevating the loaded thigh simultaneously, allowing the sweep to complete. Repeat 10-15 times per side, emphasizing the coordination of fall, hook lift, and underhook drive as a single explosive movement.

Phase 3: Coming Up on Top - Technical standup into side control after the elevation Add the finish to the rep. Drill rolling the partner through, posting your free hand, technical-standing-up, and chasing the underhook into a chest-to-chest crossface side control under light resistance. The objective is to never finish the rep on your back.

Phase 4: Counter Recognition - Reading whizzer, wide base, and head-push defenses Partner actively defends with the common counters - whizzer and drive, wide far-side base, head push and hip retreat. Practice branching to the appropriate response: arm drag to the back, dogfight back take, or half-guard and deep-half retention. Emphasis on reacting to the defense rather than forcing the original sweep.

Phase 5: Live Butterfly Sparring - Timing the sweep during passing and standing attempts with full resistance Partner attempts to pass your butterfly guard or stand up with full resistance while you hunt underhook sweep opportunities. Focus on recognizing weight-forward windows and chaining the sweep into back takes and arm drags based on their live reactions. Track which defenses cause the most trouble and build specific solutions.

Safety Considerations

What are the safety concerns for Underhook Sweep?

The butterfly underhook sweep is a low-risk technique involving no joint locks or chokes, but a few precautions apply. Because the finish elevates and rotates your partner over your shoulder, control the speed of the lift so they are not dropped onto their head or neck - guide the landing rather than launching them. When your underhook is whizzered, do not force the arm against the resistance, as this stresses the shoulder joint; branch to a back take or recover position instead. Keep your head out from under your partner’s body during the roll-through, and ensure adequate mat space so the reversal does not carry either player off the training area. When drilling with less experienced partners, scale your explosiveness and let them feel the mechanics before adding speed.

Underhook Sweep Attacker

Outcomes