So they weaseled (or muscled) their way out of the Americana. Good.
If you’ve never been hit with this miserable armbar out of side control, consider yourself lucky. Invisible Jiu Jitsu refers to it as the “Surprise Scream Tap Armbar” for a reason, cuz it is fast and nearly impossible to defend given how isolated the arm is.
The set up is a failed armbar or kimura out of side control. When your opponent straightens their arm to defend, you shift your elbows and chest forward, and apply the armbar. Make sure your elbows–the “bar” –are stacked close and tight under theirs to give you room to work. Here’s the nuanced breakdown: