Playbooks

Spot Y Cross out of Shotgun Spread Y-Flex Wk sends the two outside receivers on deep clear-out routes, one running a corner from the far side and one running a deep dig from the near side, to open up the middle of the field. The Y (tight end) runs the namesake crosser underneath from the backside, working across the formation on a shallow drag angle, while the inside receiver next to him fires a quick corner/flag route into the flat to hold the underneath defender. This is a classic Cover 3 beater built on the spot concept, with the crosser giving you a built-in answer versus man coverage since it creates natural rub traffic. Primary progression is flat/corner route first as a quick outlet, then working to the Y crosser as it clears the box, with the deep dig and corner as later developing shots if the defense bites on the underneath stuff.
Key the middle linebacker and weakside linebacker depth at the snap, since a shallow drop from either defender signals they are sitting on the crosser and you need to check to the flat route instead. Watch the strong safety pre-snap alignment, if he is shaded deep and outside it usually means Cover 3 or Cover 4 shell, both of which the crossing route and dig are designed to split. User-controlled defenders who stay home in the middle of the field (lurk technique) are the biggest threat to this concept, so if you see a defender sitting in that throwing lane, hold the ball and reset to the flat or corner route instead of forcing the crosser. Man coverage with no safety help over the middle is where this play wins most consistently, since the crosser's rub action creates natural separation against man defenders trailing from depth. Cover 2 with sticky corners and a rover-style linebacker sitting underneath can take away both the flat route and the crosser, so if you diagnose Cover 2 pre-snap look to work the deep dig or corner route on the backside instead.
Use pre-snap motion or a quick peek at the safety alignment to confirm single-high versus two-high before the snap, since this concept is designed to punish Cover 3 rotation. If you see man coverage with no safety help over the crosser, work the Y Cross low to high and expect natural separation off the rub. Hot route the flat/corner defender's man to a quick out if you are facing an aggressive slot blitz, since that route sits right in the blitzer's vacated lane. This play shines on third and medium or third and long because the crosser and dig give you two levels to move the chains, so pair it with a quick-hitting concept like Quick Slants earlier in a series to bait linebackers into sitting shallow, then hit the crosser behind them. Against zone-heavy opponents, sequence this with Four Verticals or PA Dagger from the same set to keep safeties honest and open passing lanes for the dig and corner routes.