Playbooks

Y Cross Flood out of Singleback Doubles Y Open lines up with two receivers to the right and the Y (tight end) attached to the formation. At the snap the backside outside receiver runs a deep vertical, the two right side receivers stack a corner route up top and a flat route underneath to create a high low flood read, and the Y runs a deep crossing route from right to left that settles in the middle of the field against zone. This is a Cover 3 beater built around the crosser sitting behind linebackers and in front of deep zone defenders, with the flood concept on the right stressing the corner and flat defenders vertically. The primary read progression starts with the Y crosser working left to right across the field, then moves to the flood side corner route, and finishes with the flat route as the checkdown.
Pre-snap check safety depth and corner alignment, two deep safeties with soft corners usually signals Cover 3 or Cover 4, which this play is designed to exploit through the crosser. Watch for a linebacker or nickel defender sitting in the middle of the field at the snap, a shallow zone drop from that defender is the key indicator he is sitting on the crosser route and you should progress to the flood side. Man coverage with a single high safety tips off Cover 1 or Cover 0, in this case user the deep half safety to take away the crosser and let your flood concept win on the outside against man matchups. Watch for a lurk defender sitting in the passing lane of the crossing route, if the defense shows a user controlled linebacker hovering in that zone hold the ball and reset to the flood side. Blitz heavy looks with the defense showing five or six rushers make the deep crosser risky since it takes time to develop, check the flat route on the flood side as a quick answer versus pressure.
Pre-snap identify whether the defense is playing zone or man before committing to your first read since the Y crosser is your bread and butter versus Cover 3 and Cover 4 zone shells.
If you see two deep safeties split evenly with the corners playing off, expect zone and prioritize the crosser sitting in the soft spot between the underneath and deep zones.
Against man coverage look to the flood concept on the right, the corner route can win against a linebacker or slower corner matched up in man, and the flat route gives you a quick answer versus a blitz.
Use hot routes to convert the backside vertical into a quick out or slant if you are facing heavy pressure looks, this keeps a receiver available on the short side for a fast throw.
Pair this play with Slants or Inside Cross in the same set to keep the defense guessing between quick horizontal concepts and the deeper crossing shot, this sets up Four Verticals later as a shell buster once the defense starts cheating toward the crosser.