In the main event of Invicta FC 5, Michelle Waterson and Jessica Penne had a grappling battle worthy of the ages. They traded positions, sweeps, and submission attempts in nearly equal measure. What really stood out though was the attempted armbar by Penne that Waterson was just barely able to survive and then the armbar that Waterson was able to use to win the match and the title.
We'll look first at the armbar Waterson had to escape in the third round. It came during a transition while Penne was on Waterson's back, Penne caught the armbar and it looked very close. Waterson is just able to survive, using what is called a "hitchhiker escape".
So above you see the attempted armbar. Penne appears to be doing everything right: she gets Waterson flat on her back, she is controlling Waterson's wrist, pinching her knees. How was this armbar not finished you might ask? Well it starts with how Penne breaks Waterson's grip on her arm, notice that Penne's right leg is in the elbow of the arm she isn't trying to armbar? Penne used that leg to push Waterson's arms apart and isolate the right arm for the armbar.
This is a perfectly legitimate way to open the arms, and it works. Waterson's arm is isolated and in danger of being broken, but Waterson is able to survive. Penne's leg remains in Waterson's elbow, giving her less control of Waterson's body but that doesn't actually matter until Penne makes a mistake.
Look for extra leverage to break the arm Penne work's Waterson's arm over to one side of her body, the same side Waterson's head is on. Normally BJJ players are taught aways to break towards the legs and not the head but going towards the head leaves the opening for a hitchhiker escape, but in this instance it would not resulted in escape if not for two things. First that Penne's right leg remained on Waterson's arm and not controlling her body, and second while looking to pass her left arm over Waterson's wrist to trap it in her arm pit to get a powerful, and gruesome, finishing position for the armbar, Penne loses conrol of Waterson's wrist for just a second.
That is all the time Waterson needs, she instantly rotates her and so her thumb is pointed down. Pointing the thumb down in this case totally negates the armbar, which works by bending the elbow joint in the wrong direction. When the thumb is pointed towards the ceiling, Penne's hips pushing up are driving the elbow in the wrong direction, hyper-extending it, but when Waterson changes the angle on her thumb it takes all that pressure off her elbow.
This thumb rotation is where the escape gets its name. If the escapee was standing straight up, you would point your thumb behind you like a hitchhiker trying to get a ride from a passing card.
From there Waterson is able to get her and on the other side of Penne's hips, rotate to her knees, and turn the escape into a takedown in a textbook finish to the escape. But all of that wouldn't have happened if Waterson wasn't able to survive the pressure on her arm. Ben Thapa spoke to a somewhat similar situation in which black magic was employed to survive a fully extended armbar in his Strikeforce: Tate Vs. Rousey Judo Chop: Ronda Rousey Armbars The Heck Out of Miesha Tate.
Another theoretically possible defense for Miesha would have been to take the Vinny Magalhaes approach to the armbar Fabricio Werdum applied upon him in the 2011 ADCC heavyweight final. Basically, Vinny got up on his side - which allows his larger frame to relieve the pressure somewhat - and then employed mystical grappling magic to allow him to tough out a super-gnarly submission being applied by one of the very best grapplers on the planet for several minutes. This "Vinny defense" is not advised for anyone who does not have the high level grappling background that Magalhaes possesses or has not made peace with the possibility of the arm being broken like what happened to Miesha Tate. Seriously, I have no idea how Vinny stayed in that for so long or eventually got out of it. Werdum did not do anything immediately and obviously wrong. That is Benson Henderson level Gumby stuff.
But that is only half the story, the other half is how Waterson turned the tables on Penne in the fourth round with an armbar of her own.
Here Waterson was, on the bottom of half guard working for a kimura one arm and then is seemed all the sudden she had an armbar on the other. Nobody seemed to know what had happened, least of all Penne. This is a prime example of grappling chess.
Waterson looks like she is going for a kimura, but it is on the wrong side of the half guard for her to really be able to finish well. Waterson appears to be using the grip to take the back from the half guard. Penne has committed her head and left arm to preventing the kimura. Even though it wasn't the best position for that submission, Penne has to respect it or it will become a danger.
Waterson sits up to take the back and Penne's only options are to drive forward and put Waterson on her back or allow her own back to be taken. Penne tries to defend the position, but because of the kimura attempt her arms are badly out of position, but that is ok because Waterson is still in half guard and not a threat to throw up an armbar.
Except, she does.
It is possible to get the armbar from a loose half guard, the key for it is that Waterson gets her left knee between her and Penne. With that knee between them Waterson is able to stretch Penne's base out, isolate the arm, and get the armbar.
To finish with here is Professor Salvatore Pace teaching both the armbar and the hitchhiker escape in the same video