BJJ Knee on stomach

Knee on stomach is a offensive sport jiu-jitsu and mixed-martial arts position. It provides you with excellent leverage for striking a downed opponent, some ability to keep them there, the ability to drain their cardiovascular reserves by putting your weight on their abdomen, and sets up numerous submissions. The inferior leg should be across their lower abdomen with the toes off the mat and the other foot placed approximately 45° in line with their shoulder. I imagine taking a kickboxing stance and rolling my knee to the floor. One of the keys to attack here, as with all submissions, is to make your opponent give you the submission. Thus:

180° arm bar

If your opponent tries to defend the knee on stomach by pushing on your knee, insert the hand on their inferior side in the "triangle" created by their arm. Lift and step over their head with the post foot, imaging that you are trying to "kick" them in the kidneys. Grab the belt or pants and sit straight down, pinching your knees together. You rotation should place you in a perpendicular position with your opponent. Control the wrist and thenar eminence.

Straight Figure 4

If you opponent tries to push off the superior leg hip overhook the arm, placing your forearm just proximal to their elbow. Grab your own forearm on the opposite side and place this hand distal to their shoulder. Arc upwards to apply pressure to the elbow.

Baseball choke

Same collar overhand grip with the superior hand, fitting the arch of thumb against their neck while pushing the kimono to open the opposite side. Underhand grip with the other side, placing the hands adjacent with one another. Keeping the wrist straight drop your inferior shoulder and arm, trying to get that elbow to the mat as you step around your opponents head. Place your superior knee on the opposite side of their head.

It is important to remember that the knee on stomach is a very dynamic, you cannot simply sit their and not expect your opponent to move reverse you. Thus it is important to be able to transition to the other side to retain your positional advantage. There are two methods to do this:

Spin

Use the superior leg to "kick" the kidneys on the opposite side, setting it up as the new inferior leg.

Jump

Place your hands on your partner, then jump straight across their setting up a new knee on stomach on the opposite side.