Playbooks

Not in any team playbook.
Mesh Sit out of Shotgun Double Wing brings two crossing routes underneath (the mesh concept) that rub against man defenders, while a third receiver sits down in the shallow zone window on the opposite side after clearing the crossers. The lone outside receiver runs a deep vertical up the sideline to hold the corner and safety, stretching the field so the mesh has room to operate underneath. This is a man beater at heart, since the two shallow crossers create natural traffic that forces defenders to fight through picks, but the sit route also gives you a built in answer versus zone if the linebackers sink under the crossers. Primary progression starts with the mesh crossers working from the near side out, then works to the sit route as the checkdown, with the deep vertical as the home run shot if the coverage is playing off or bites on the underneath routes.
Watch for a single high safety shell presnap, which usually signals man coverage underneath and tells you the mesh crossers will draw natural picks against trailing defenders. If the safety rotates down into the box or shows two deep at the snap, expect zone coverage, and prioritize the sit route sitting down in the soft spot between levels. Key the middle linebacker depth at the snap, since a shallow drop from the mike means he can undercut the sit route, forcing you to look to the deep vertical instead. Identify blitz packages by counting box defenders pre-snap, and if you see six or more in the box, get the ball out quickly on the shorter mesh crosser before the pocket collapses. Cover 3 zone with a hard flat corner can squeeze the sit route, so be ready to reset your eyes to the mesh crossers working away from the flat defender's leverage.
Look for man coverage indicators pre-snap such as tight press corners or a single high safety shaded to one side before snapping this play, since the mesh concept thrives against man to man leverage.
Use motion across the formation if available to confirm man versus zone by watching if a defender follows the receiver in motion.
Hot route the sit route to a deeper curl if you see linebackers sitting low in zone drops, since that adjustment gives you a bigger throwing window against zone shells.
Pair this play with Mtn PA Slide or QB Power out of the same Double Wing set to keep the defense honest on run action before dialing up Mesh Sit on obvious passing downs.
Best used on second or third and medium since the mesh routes need a few seconds to develop and clear the traffic, so avoid calling this on third and long against aggressive blitz packages.