Half guard traps one of your partner's legs between yours, which stalls the pass but leaves your upper body exposed. Two families answer that problem. The underhook game puts your shoulder under theirs so you can come up onto an elbow and threaten a sweep or the back. The knee shield game inserts a shin across their hips to hold them at range and rebuild frames. Both fail the moment your back settles flat.
Key points
- Turn onto your side facing your partner, since a flat half guard invites the crossface pressure that ends the position.
- Win the underhook and immediately post on your elbow, because an underhook taken with your back on the mat is not yet useful.
- A knee shield works when the shin crosses their hip line and your bottom leg still hooks, giving you two barriers instead of one.
- Fight the crossface with a frame on their shoulder or biceps, because if your head is turned away your hips cannot follow anything.
- Trap the far ankle or block the near knee so they cannot free the leg and step directly over into mount.
Common mistakes
- Hugging the trapped leg with both arms while lying flat, which surrenders the underhook and converts half guard into a slow pin.
- Allowing them a deep crossface plus an underhook of their own, after which the pass usually completes without much further resistance.
- Straightening the knee shield leg, which lets them press it down and close the distance in a single movement.
Put it into practice
Underhook battle
- Start in bottom half guard with neither partner holding an underhook and set a ninety-second clock.
- Compete only for the underhook and head position, with no sweeps, passes or submissions allowed.
- Reset from a knee shield, the top player trying to flatten the shin and the bottom player trying to keep it across the hip.
- Swap roles, then identify which frame collapsed first on every exchange you lost.
half guardunderhookknee shieldcrossface