Playbooks

Verticals Y Cross out of Shotgun Trey Y-Flex Str sends three receivers vertically up the seams and sideline while the Y (TE) runs a deep cross from the opposite side all the way across the field, and the backside X releases on a stick/curl route breaking outside. The lone RB stays in to check release before working outward as a late outlet on the boundary. This is a five man route concept with no play-action or run elements, built as a Cover 2 and Cover 3 beater where the deep cross is the primary read since it sits down or continues working across the middle behind linebackers and in front of deep safeties, with the streaking verticals used to hold the safeties and clear space underneath for the crosser.
Pre-snap, check safety depth and width, if both safeties are deep and split evenly this indicates Cover 2 or Cover 4 and the crosser will need extra time to develop. Watch the middle linebacker's initial drop, if he sinks deep to help on verticals he opens the crossing lane, if he sits shallow he can undercut the Y cross and jump the throw. Man coverage shells with no safety help over the top get exposed by the verticals, so if you see man alignment with press corners expect the deep routes to win instead of the cross. Use a spy or rat linebacker underneath to lurk the crossing route since that is the built in answer to shut down the primary read. Blitz packages that bring extra rushers leave this play vulnerable to a hot throw, so if the RB releases late as an outlet be ready to jump that check down with a user linebacker.
Use this on early downs or second and long when defenses are more likely to sit in two high shells rather than blitz.
Pre-snap, identify single high versus two high safeties because the four verts style spacing forces safeties to declare and opens throwing lanes for the Y cross.
If you see Cover 3 with a deep middle safety, target the Y cross as it crosses the field behind the linebackers and in front of the safety before he can flow over.
Against Cover 2, work the outside vertical to hold the corner and hit the crosser in the void between the flat defender and the deep safety.
Pair this play with RPO Peek Slant or RPO Zone Peek Pop earlier in a drive to get defenders keying on quick game before hitting them with the deeper cross concept for an explosive play.