Playbooks

Empty Vertical is a five-man route empty pass concept out of Trey Y-Flex that stretches the field horizontally and vertically with no backfield help, forcing the defense to declare its coverage shell immediately. From the diagram, the two receivers on the left run a corner route and a stack of an out plus a shallow flat/angle route, the middle vertical stem runs a straight seam to the top of the screen, the slot receiver on the right runs a seam that breaks vertically, and the outside receiver on the right runs a flat route followed by a corner breaking up the sideline. With five true vertical or vertical-breaking stems and one flat route as a built-in checkdown, this is a classic four verts variant designed to attack both Cover 2 and Cover 3 shells. The primary read progression starts with the deep middle seam against Cover 3, works to the corner routes against Cover 2, and comes down to the flat route as the built-in outlet versus tight man coverage.
Watch the free safety depth and width pre-snap, since a shaded safety toward the trips side signals help over the seam and corner combo on that end. If both safeties are aligned deep and outside the numbers, expect Cover 2 and prioritize the corner routes over the seams. A single high safety with corners playing outside leverage indicates Cover 3, meaning the middle seam is the primary answer before the safety can rotate over. Post-snap, track any user-controlled defender dropping into the deep middle hole, since a rangy lurking safety can undercut the seam and bait a turnover. Watch linebacker depth at the snap, since a delayed blitz or a linebacker sinking hard into a zone drop can close the throwing window on the seam route and force the checkdown to the flat.
Pre-snap, identify whether the safeties are showing two-high or rotating to single-high, since this concept is built to punish both shells differently. Against Cover 3, key on the middle seam splitting the two deep hole defenders and throw it before the safety can get over the top. Against Cover 2, work the corner routes into the void between the corner and safety, especially on the right side where the flat-to-corner combo stresses the flat defender. Use motion pre-snap to identify man coverage, and if you see a defender follow across the formation, hot route the flat route into a quick option or throw it early as a rhythm completion. Pair this play with Empty Stick or Levels Out from the same set to keep the defense guessing between vertical shots and quick game, since the formation and personnel look identical until the routes break.