If he is on your right side (your on your back) and his right knee (most common is on the gut looking to pass guard for mount. Looks a bit like your going for north and south this one but should make sense.
Hook your right arm behind his left leg (depending on where it is) and go for a toe hold or knee bar so long as you can push or pull him over the top of you. This works a fair bit.
Other option is if you cant get other go for pusing off his nearest hip to stop him gaining the mount position and if you can get a knee up to be inside his legs controlling his position a bit better take hold of his leg or Gi bottoms (with hand on hip) work best if he has them and with which ever leg is best push him off you but keeping hold of the leg should cause him to fall away from you leaving you open for ankle locks or toe holds (toe Hold often requires a bit of positioning!)
I didn't read any of the post exepts Strong Machine, but here are two i use.
First Simple one. I use your basic shrimp escape except my arm that is closest to him reaches underneath his shin that is across my body and i grab the top of his foot. When i shrimp my hips away from him i throw my leg closest to his body underneath my other leg and come up to all fours beside him. Then i finish with an outside single leg sweep.
Second. Mike Fowler shows this on the grappling gameplan DVD. Shrimp to your side. Bring the knee farthest from his body behind his knee that he is riding on. Farthest hand from his body goes to his far leg and just roll back. Should sweep him to crossbody
On that Fowler method are you saying you reach around him and grab his posting leg like in a similar halfguard reversal?
You don't so much reach around his leg as you just post your hand against his knee. OOPS I just re-read my post. I ment to say the arm closest to his body is the one that post on his extended knee and the other just helps trap his knee to yours
From a clinch, often with the opponent holding me head under their own/against the collar bone sort of thing before they put the knee in I usually curl my hands into fists and jam them into the hips.
Typically, they'll try and twist their hips, I dig harder, get them off balance and try to launch my own knee strike. Meh, not very effective.
By striking them on the inside of their inner thigh, along the chi meridian, you can kill them by sending the chi back into their brain.
Sorry, couldn't resist.
Are we talking about MMA competition or street defense? I was practicing this in class a few days ago, and from the way my guy was on me, the most obvious first thing seemed like a quick shot to the groin. The top man had knee on stomach(actually, pressing into solar plexus, shin was resting on stomach), grabbing clothing w/ left and punching w/ right. Drill was deflect to your right + slide head & shoulders to left as much as possible, then punch(or I guess you could grab&squeeze) groin. From there, an arm lock(of sorts, not sure what the hell it's called or how useful it'd be) where right forearm hit 'folding' side of elbow & pushed down, left hand grabbed punching wrist & folded arm up. Right hand grabs your own left arm, and you pull down & left while 'flipping' to your side (not really a roll,just sorta 'shift' over till your on left side. If this tosses him off, since I'm better at stand up I figured best thing to do was get the hell up & away. Is this plausible?
If I'm in knee on stomach in a real fight I am dropping bombs on your face.Or at least trying to.Sure a groin shot can hurt alot if it lands perfectly. but the angle the bottom guy is at isn't the best.
I dunno, I think if punches are flying at my nose as my head is on the pavement that that should be my immediate concern, not takling an arm away from my face to go at your groin.
In a real fight punches come in bunches and with commitment.Most guys who are in an advantageous position just keep raining them down one after another.I don't see the bottom guy getting the chance to compose himself enough to even think about striking back.
All the moves above are good and well for grappling.
But even in MMA(let alone the street) if someone gets his head up enough to get to a kneeride he can knock me out with punches, not just annoy me as if he's lower.
I will bridge like a madman and maybe try to grab a leg and drive him down as if doing a single leg.
I would never try most of the sophisticated escapes listed above.