Playbooks

Mtn PA Double Posts is a play-action pass out of Shotgun Split Slot Offset that sells run action before releasing two vertical post routes on the right side while the outside receiver and a shallow crosser clear out the left. The diagram shows the far right X running straight up and breaking into a deep post, the inside receiver next to him running a similar but slightly shorter post underneath, and on the left the outside receiver runs a deep comeback while the tight end or slot man motions across on a shallow drag underneath everything. This is a man beater built to attack safeties who bite on the run fake, with the double post stacking a two level crossing threat that the QB reads from the deepest post down to the shorter post as the primary progression.
Watch for single high safety looks pre-snap, this play is designed to exploit Cover 1 and Cover 3 because the double post overloads one side of the deep zone or the deep third defender. Track linebacker depth at the snap, if they bite hard on the run fake the underneath drag and shallow crosser will be wide open before the safety can rotate over. Identify user controlled defenders lurking in the middle of the field, a smart user will sit in the passing lane between the two posts and jump the shorter route, so patience on the throw is key. Cover 2 and Cover 4 shells with two deep safeties are the best defense against this play since they can bracket both posts, look for the QB to check down to the comeback route in that situation. Watch blitz timing off the edge, if the defense brings pressure the play-action fake buys extra time, but a fast interior blitz can disrupt the QB before the deep posts fully develop.
Run this on early downs like first or second and medium when defenses are keyed up to stop the run so the play-action freeze has maximum effect on linebackers and safeties.
Check the safety alignment before the snap, if you see two high safeties sitting deep the double post concept will collapse the throwing window on one so look to hit the underneath drag or comeback instead.
Use the motion man to identify man versus zone coverage before the snap, if the defender follows across the formation you know it is man and the posts will have single coverage to win against.
Pair this with Mtn PA Stutter Go or Mtn Stutter Go in the same set so defenders start respecting the deep shot off similar formation and motion, then hit them with this double post when they jump the comeback route.
Hot route the shallow drag into a deeper option against zone shells with linebackers sitting in the middle, since that route can get clogged if the defense drops a linebacker into the throwing lane.