The knee cut pass

Position and problem

The opponent is on their back or side with one leg between yours, in half guard or in the tail end of an open guard. You have part of a pass but not the pass. From here the knee cut offers a short, direct route: instead of going around the legs, you cut through the space between them and land on the far side, chest first. The problem is that the same route puts you in reach of an underhook, and a knee cut that arrives without the upper body settled arrives into a sweep. The terms knee cut and knee slice refer to the same pass; both are common and neither is more correct.

Objective

Cut the near knee across the opponent's thigh and arrive chest-to-chest on the far side with their legs behind you.

Core concept

The knee is not what passes the guard — the shoulder is. The cut supplies a wedge that stops the bottom player replacing their leg, but the pass completes because your chest and head have taken the far-side connection and killed their ability to come up. That is why the standard failure of the knee cut is not a leg problem: it is conceding the underhook and getting swept by someone whose leg you had already cleared. Sequence the pass upper body first, then the cut, and the leg work becomes almost automatic. In no-gi this ordering matters more, because without cloth to hold, the bottom player's underhook is the most durable connection available to them.

Key mechanics

1. 01Win the near-side underhook or a strong crossface before the knee travels. Whoever has the underhook decides whether this ends as a pass or a sweep.
2. 02Cut on a diagonal toward their far hip, not straight down toward the mat. A vertical knee drive lands you in their half guard again with your shin trapped.
3. 03Keep the trailing foot's toes on the mat and the hips low. A knee cut done high, with the trailing knee off the floor, hands them the space to recover a hook.
4. 04Clear their foot before you drive. If their hook or lace is still on your leg, cutting through is fighting a leg that is attached to you rather than passing one that is free.
5. 05Bring your head to the far side of theirs as the knee lands. Head position on the far side removes the space they need to sit up.
6. 06Have the counter-route ready. When they underhook and come up, the knee cut should convert — to a back take, to a switch to the other side, to re-establishing a top position — rather than being defended in place.

Common errors

• ×Starting the knee cut with no upper-body control, which arrives past their legs and directly into their underhook.
• ×Driving the knee straight down instead of diagonally, so the shin ends up trapped and the pass stalls in half guard.
• ×Passing high, with the hips off the mat and the trailing knee up, which gives the bottom player room to re-insert a knee or a hook.
• ×Racing the cut before the bottom leg is free, so the pass is being run through an attachment that is still live.
• ×Continuing to drive forward once the bottom player has come up on the underhook, when the position has already become a scramble that wants a different answer.

Safety

The specific injury exposure in the knee cut belongs to the person underneath. When their foot is still hooked or laced on your leg and you rotate and drive across, the rotation arrives at their knee, which is fixed at one end by their hook and loaded at the other by your body weight. Clear the foot before you cut, and stop cutting if you feel a leg resisting in a direction it should not be able to resist. When you are underneath, do not hold a hook while a passer is rotating through it — let it go and recover. The passer's own knee sliding across the mat under load is the other, much smaller cost of this pass; it is a friction problem, and the usual answer is to slide on the shin rather than grind on the kneecap.

Training progression

1. 01Static: partner lies in half guard with no resistance. Establish the underhook and the crossface first, then cut the knee across slowly and stop when your chest lands.
2. 02Cooperative: partner offers a token underhook attempt each repetition so you practise winning the upper body before the leg moves.
3. 03Constrained game: you may only pass with the knee cut; the bottom player may only defend with the underhook and the knee shield. Restart on either completion.
4. 04Conversion drill: partner deliberately comes up on the underhook every time. Practise the two conversions — going behind them, or switching to the other side — rather than resisting.
5. 05Positional sparring: start in half guard, full resistance, top player restricted to the knee cut family. Swap roles every three minutes.
6. 06Live rounds: note whether your knee cuts are starting from a settled upper body or from a leg opportunity you saw and chased.

Related entries

• The knee shield
• Inside position
• Connection in open guard