One of the most common things to happen when someone goes for an omoplata is for your opponent to try to roll out of it right away.
What a lot of people don't realize they can do, is they can actually attack their opponent's knee in the process. It's a slick kneebar that catches them off guard.
//www.youtube.com/watch?v=SknhwRwVxvs
Thanks for watching,
Jason Scully
I started doing this a couple of weeks ago.
I'd never been taught it, but it just kind of happened during a roll, now I use it all the time.
Cool vid and well explained, as usual. VU 
Been using this for a while also. Like the guy above said I stumbled into on accident! I will also get the guy to roll by attempting a toe hold.
Same thing actually happened to me years ago too. I was going for an omoplata on somebody and when they went to go roll out I fell right into this kneebar.
That was like 6 years ago
So simple and obvious when you see it... I can't believe that I don't think I've ever thought about it before! Thanks.
How much success do you have with it? Does the opponent turn his leg often before you have a chance to pinch everything tight?
Meatgrinder -The success rate is higher than most may think the reasons for this are:So simple and obvious when you see it... I can't believe that I don't think I've ever thought about it before! Thanks.
How much success do you have with it? Does the opponent turn his leg often before you have a chance to pinch everything tight?
1. The person rolling isn't expecting you to kneebar them
2. Your mobility should generally be better then theirs
3. The under arm kneebar in all kneebar cases (when their leg is on top of you but not on the bottom) is extremely strong and makes it much harder for them to turn their leg due to the amount of pressure on their.
Main thing is your timing should be faster then theirs.
I've hit this on a pretty well known black belt before. They had know idea what happened.
Just using the elbow to stop him seems very close to putting the arm inside, and exposing yourself to a omaplata as well.
Any thoughts from you guys in using the outside arm to catch the opponents leg, then continuing the transition to kneebar?
Also, if the rotate their leg inward, I have hit a few nasty outside heel hook counters off of it. Anyone else have a similar setup as well? 
Pretty cool technique. I first saw it at Erik Paulsons seminar in the UK in 2005. Its amazing how many new innovations particularly leg-lock variations Paulson has been doing for years.
BTTMike - I like the heelhook transition off of the kneebar setup also.
Denis Kelly -Yeah, Eric Paulson did this at a seminar i went to back in 2001.Pretty cool technique. I first saw it at Erik Paulsons seminar in the UK in 2005. Its amazing how many new innovations particularly leg-lock variations Paulson has been doing for years.
Very slick Jason! I love it. I'm going to practice this right away.
Thanks for sharing!
nice vid, I never thought of using this counter before...I seem to be in the minority