Z -- Flanker: Lines up wide right and runs a 3 route, a 10- to 12-yard square-out pattern with a hard cut. If he draws press coverage from the corner, the Z converts the route to a hinge, or sharp comeback, at 15 yards. Against press coverage by the cornerback and two-deep coverage by a safety, the route becomes a fade, or a deep go route.
Y -- Tight end: Runs an inside 8, a deep post pattern. If the middle of the field is closed (MOFC), he will run a 12-yard inside cut; if the middle of the field is open (MOFO), he will nod at the linebacker and run a post. Nod means to go hard at the linebacker to force him off coverage.
X -- Split end: Lines up wide left and runs a 3 route, a hard 10- to 12-yard square-out pattern. If he draws press coverage from the corner, the X converts the route to a hinge, or sharp comeback, at 10 to 15 yards. Against press coverage by the cornerback and two-deep coverage by the safeties, the route becomes a fade, or a deep go route.
H -- Fullback: Must pass-protect first (Fox), then run route. The fullback picks up any inside blitzers, then runs short route up middle and to the left.
R -- Running back: Must pass-protect first (Fox), then run route. The running back picks up blitzers from the right side of the offense, then fades into the right flat on a short route.
THE INSTALLATION OF PFB DOUBLE SQUARE OUT
? In this variation the tight end (Y) goes in motion (dotted line) then runs his route across the middle, working between the linebackers and the deep safety (inset).
? The quarterback takes a five-step drop and prepares to throw to the flanker (X), who runs an out pattern and cuts off his route in front of the cornerback (inset), at 12 yards.