Playbooks

Verticals Under is a four verticals concept out of Shotgun Empty Strong Slots that stretches the field vertically while sitting one underneath crosser to hold linebackers. Both outside receivers and the inside slot run straight verticals up the seams and sideline, while the middle receiver runs an under route crossing the field low as a shallow window against zone drops. There is no run action or blocking scheme since this is an empty backfield pass play designed as a Cover 2 and Cover 3 beater, attacking the deep middle void and the seams between the corners and safeties. The primary read progression starts with the deep seam route to the play side, moves to the opposite vertical if the safety rotates away, and comes down to the under route as the checkdown against tight zone drops.
Pre-snap, check safety depth and spacing since two safeties splitting deep signals Cover 2 while a single deep safety centered over the ball signals Cover 3. Watch cornerback alignment on the outside verticals, since press corners with no safety help over the top invite a user pick or jump on the seam route. Post-snap, key the middle linebacker's drop, since a shallow drop into the under route window shuts down the checkdown but opens the seams behind him. Beware of a user controlled deep safety sitting in the middle of the field, since that lurk threat can jump the crossing under route or rob the inside seam. Blitz packages that bring extra rushers off the edge with no deep safety help are the biggest risk to this play, since the four verticals concept relies on the quarterback having time to work through the deep read progression.
Pre-snap, identify whether the defense shows two deep safeties or one high safety before the snap since this concept is built to exploit both Cover 2 and Cover 3 shells.
Against Cover 2, target the seam routes between the corner and safety since the four verticals concept overloads the deep half defenders and forces a choice.
Against Cover 3, work the under route as your first read if the middle linebacker sits shallow, then climb to the vertical on the opposite hash if the deep third defender bites on the crosser.
Use hot routes to convert one of the outside verticals into a comeback or sit route if you diagnose heavy zone drop from the flat defenders, giving you a quick answer against Cover 4 shells.
Pair this play with Option Stick Nod or Corner Pivot In from the same Empty Strong Slots set to keep defenses honest, since those quick game concepts punish teams that sit deep to defend the verticals.