The Underhook Pass is a fundamental pressure passing technique used to advance from half guard top position to side control. This pass exploits the powerful control provided by securing an underhook on the bottom player’s far side, combined with strategic weight distribution and hip pressure to flatten the opponent and clear the leg entanglement. The technique is built on the principle of controlling the opponent’s shoulder and hip simultaneously, creating a cross-body pressure system that limits their defensive frames and movement options. The underhook provides both offensive control and defensive protection, preventing the bottom player from establishing their own underhook or recovering full guard. This pass is particularly effective against players who rely on knee shield or traditional half guard retention, as it addresses their primary defensive structures through systematic breakdown and methodical advancement.
Starting Position: Half Guard Ending Position: Side Control Success Rates: Beginner 45%, Intermediate 60%, Advanced 75%
Key Principles
- Secure underhook on far side before initiating pass
- Drive shoulder pressure into opponent’s chest to flatten
- Control opponent’s near hip with free hand to prevent re-guard
- Keep base wide and weight distributed forward
- Clear trapped leg by driving knee across opponent’s thigh
- Maintain chest-to-chest pressure throughout transition
- Prevent opponent’s underhook battle at all costs
Prerequisites
- Top position in opponent’s half guard with leg trapped
- Underhook secured on opponent’s far side arm
- Head positioned on opponent’s chest, not allowing space
- Wide base with free leg posted for stability
- Opponent’s frames neutralized or controlled
- Weight forward, hips low and heavy on opponent
Execution Steps
- Secure the underhook: From half guard top, thread your arm under opponent’s far armpit, securing a deep underhook. Your shoulder should drive into their chest while your hand reaches across their back, ideally gripping their far lat or belt. This underhook is the cornerstone of the entire passing sequence. (Timing: Establish before opponent can frame or create distance)
- Establish crossface pressure: Place your head on opponent’s chest, driving your shoulder into their near pectoral muscle. This crossface pressure prevents them from turning into you or establishing their own underhook. Your ear should be tight to their sternum, minimizing space for their frames. (Timing: Immediately after securing underhook)
- Control the near hip: With your free hand (non-underhook side), establish a firm grip on opponent’s near hip, pants, or belt. This grip prevents them from using hip movement to recover guard or create the angle needed for sweeps. Your palm should be facing down with fingers digging into their hip. (Timing: Concurrent with crossface establishment)
- Flatten opponent’s posture: Drive your weight forward through your shoulder and chest, forcing opponent flat to their back. Simultaneously pull with your underhook and push with your crossface, creating opposing forces that collapse their defensive structure. Their shoulder blades should be pinned to the mat. (Timing: Progressive pressure, not explosive)
- Clear the trapped leg: With opponent flattened, begin extracting your trapped leg by driving your knee across their thigh toward their hip. Maintain all upper body pressure while subtly shifting your hips backward. The key is small, methodical movements rather than explosive yanking that creates space. (Timing: Only when opponent is fully flattened)
- Step over to side control: Once your knee clears their hip, step your free leg over their legs and establish side control. Keep your underhook and crossface pressure throughout the transition. Your chest should never leave their chest during this movement, maintaining constant pressure and connection. (Timing: Smooth transition maintaining all control points)
- Consolidate side control: Secure standard side control position with your underhook transitioning to far side control, your head positioned on the near side of their head, and your hips low and heavy. Establish all standard side control grips and pressure before considering further advancement or submission attacks. (Timing: Immediate consolidation after clearing legs)
Opponent Counters
- Bottom player establishes their own underhook, creating an underhook battle and preventing pass progression (Effectiveness: High) - Your Response: Immediately switch to whizzer control on their underhook arm, driving your weight into their shoulder while using your free hand to strip their grip or transition to alternative passes like the knee slice
- Strong knee shield frame preventing chest-to-chest pressure and flattening (Effectiveness: High) - Your Response: Address the knee shield by controlling the knee with your free hand, driving it to the mat while maintaining underhook pressure. Alternatively, transition to knee cut pass or smash pass variations
- Bottom player turns away (going to turtle) to escape pressure and leg clear (Effectiveness: Medium) - Your Response: Follow their rotation, maintaining the underhook and transitioning to back attack or using the momentum to complete the pass to opposite side control
- Electric chair or lockdown control on trapped leg, preventing extraction (Effectiveness: Medium) - Your Response: Focus on breaking the lockdown first by driving your trapped ankle to the mat and extracting your foot. Maintain upper body control throughout to prevent sweeps
- Bottom player bridges explosively to create space and re-establish guard (Effectiveness: Low) - Your Response: Ride the bridge by staying heavy and connected, allowing your body to move with theirs while maintaining underhook and crossface. As they come down from the bridge, increase pressure
Test Your Knowledge
Q1: Why is securing the underhook before attempting to flatten the opponent critical to the success of this pass? A: The underhook provides the primary control mechanism that prevents the bottom player from turning into you or establishing their own underhook. Without it, the opponent can easily create frames, turn to face you, or initiate sweeps. The underhook acts as both offensive control (allowing you to manipulate their posture) and defensive protection (preventing their offensive options from half guard). Attempting to flatten without the underhook results in a scramble situation where the bottom player has equal or superior control options.
Q2: What is the primary purpose of controlling the opponent’s near hip during the underhook pass, and what happens if this control is neglected? A: Controlling the near hip prevents the opponent from using hip escape (shrimping) movements to create the angle and distance needed to recover full guard or initiate sweeps. The hip is the mobility center of the bottom player’s defensive movement. Without this control, even with good underhook and crossface, the opponent can shrimp away, creating space to re-establish their guard structure or insert knee shields. The near hip control works in conjunction with the underhook to create a pinning system that immobilizes the opponent’s core.
Q3: Explain the biomechanical principle behind driving your shoulder into the opponent’s chest while maintaining the underhook, and how this creates a flattening effect? A: The shoulder drive creates a cross-body lever system where opposing forces work simultaneously. The underhook pulls their far shoulder toward you while your near shoulder pushes their near shoulder away from you. This creates rotational torque that flattens their spine against the mat. Additionally, the shoulder pressure on the chest restricts diaphragm expansion, making it uncomfortable to maintain a defensive posture on their side. The weight distribution through the shoulder transfers your body mass efficiently onto their frame, collapsing their structure without requiring you to lift your hips, which would create escape space.
Q4: How should you respond if the opponent establishes a lockdown on your trapped leg while you have the underhook position? A: First, maintain all upper body control (underhook and crossface) to prevent sweeps while addressing the lockdown. Focus on breaking the lockdown by driving your trapped ankle toward the mat, creating a figure-four breaking position with your legs. Keep your weight forward and low to prevent the opponent from using the lockdown to create angles for electric chair or other attacks. If necessary, temporarily abandon leg extraction and work to break the lockdown first, potentially by driving your free knee across their body to relieve pressure on the trapped leg, then return to standard passing mechanics once the lockdown is broken.
Q5: What are the key differences in executing the underhook pass against a knee shield half guard versus a traditional half guard with no shield? A: Against knee shield, the primary challenge is dealing with the extended frame that prevents chest-to-chest pressure. You must first address the knee shield by either controlling the knee and driving it to the mat, stepping over it, or transitioning to a different passing angle (like knee cut). The underhook remains important but the crossface pressure is harder to establish initially. Against traditional half guard without knee shield, you can more directly establish chest-to-chest pressure and begin the flattening process immediately. The traditional half guard allows faster entry into the flattening phase but may have stronger lockdown or underhook battle threats, while knee shield provides more initial defensive structure but less sweep threat once bypassed.
Q6: Why is it important to keep your base wide with your free leg during the underhook pass, and how does this affect your passing mechanics? A: A wide base with the free leg posted creates stability against the opponent’s bridging, hip bump, and off-balancing attempts. With your weight forward and one leg trapped, you’re potentially vulnerable to sweeps if your base is narrow. The wide post allows you to distribute weight effectively while maintaining mobility to adjust to the opponent’s movements. It also creates the angle needed to drive your trapped knee across their thigh during leg extraction. A narrow base makes you top-heavy and easy to tip over, while a wide base allows you to stay heavy on top while remaining structurally sound and able to generate the hip movement needed to clear your trapped leg.
Safety Considerations
The underhook pass is generally a safe technique when executed properly, but practitioners should be aware of several safety considerations. Avoid driving excessive pressure into the opponent’s neck or head, as the crossface should target the chest and shoulder, not the cervical spine. When extracting the trapped leg, move methodically to avoid hyperextending your own or your opponent’s knee joints. Be cautious of cranking or twisting motions with the underhook that could stress the opponent’s shoulder joint. When drilling, partners should communicate about pressure levels, especially when learning the flattening mechanics. Beginners should focus on positional control rather than explosive movements that could result in knee or shoulder injuries.
Position Integration
The underhook pass is a cornerstone technique in the pressure passing system and serves as a fundamental connection point between half guard top and side control. It integrates seamlessly with other half guard passing approaches, allowing practitioners to chain together multiple passing sequences based on the opponent’s defensive responses. The underhook position naturally transitions to knee cut passes, long step passes, or back takes depending on how the opponent defends. This pass is particularly important in gi grappling where grips enhance the underhook control, but remains highly effective in no-gi through proper body mechanics. The underhook pass teaches essential principles of pressure application, weight distribution, and systematic position advancement that apply broadly across all top game scenarios.
Expert Insights
- Danaher System: The underhook pass represents one of the most biomechanically efficient methods of advancing past the half guard because it addresses the fundamental problem of guard passing: controlling the opponent’s ability to create frames and angles. The underhook creates what I call a ‘control hierarchy’ where you dominate the far side connection while the crossface neutralizes the near side. This dual control system collapses the opponent’s defensive structure systematically. The key technical insight is understanding that the pass occurs not through explosive force but through progressive pressure application. Each component - the underhook, the crossface, the hip control - creates a compound effect where the sum is greater than the parts. When students struggle with this pass, it’s almost always because they’re trying to pass with their legs before they’ve established dominance with their upper body. The legs are merely the final technical detail; the real passing occurs in the chest-to-chest pressure battle.
- Gordon Ryan: In competition, the underhook pass is my go-to technique from half guard because it’s the highest percentage option against elite-level defenders. What makes it competition-proven is that it works even when your opponent knows it’s coming. The pressure and control are so dominant that awareness doesn’t equal effective defense. The critical factor most people miss is the timing of when to commit to the leg extraction. I see a lot of guys trying to yank their leg out while the opponent is still mobile. That’s low percentage. You need to make them completely flat first, even if it takes 30-40 seconds of grinding pressure. Once they’re flat, the leg clears easily. In my matches, I’ll often use the threat of the underhook pass to set up other attacks. If they’re overly defensive about their far side underhook, I can switch to knee cut passes. If they turn away to avoid the pressure, I take the back. The underhook position is a control position first, passing position second, which is why it’s so reliable under pressure.
- Eddie Bravo: The underhook pass is interesting because it’s one of the few traditional passing techniques that works equally well in gi and no-gi, though we approach it slightly differently in the 10th Planet system. Without the gi grips, the underhook becomes even more critical because it’s your primary connection point. We emphasize what I call the ‘shoulder of justice’ - driving that shoulder into their chest like you’re trying to put it through the mat. That shoulder pressure is everything. One innovation we’ve added is being willing to transition to back takes more aggressively. In traditional approaches, if the guy turns away, it’s sometimes seen as a problem. For us, that’s perfect - we follow the turn and take the back. The underhook gives you the connection to follow wherever they go. We also use the underhook position to set up Darce chokes when guys fight hard for their underhook. If they’re exposing their neck fighting the underhook battle, we’re happy to switch to the submission. The key is being fluid and opportunistic rather than rigidly committed to the pass.