Playbooks

Empty Mtn HB Swing lines up in an empty backfield out of Shotgun Normal Y Off Close, sending the halfback out wide to the flat on a swing route while a receiver runs a mini out and up creating a two level stretch on the boundary side. The lone underneath route from the slot man breaks outside then works vertically, occupying underneath defenders and clearing space for the swing. This is a zone beater designed to attack flat defenders and outside linebackers with horizontal stretch, and the primary read progression starts with the HB swing as the checkdown and hot route against pressure, then works to the out and up breaking route if the flat is capped and a vertical throwing lane opens.
Identify the flat defender or outside linebacker responsible for the boundary side before the snap, his depth and width dictate whether the swing route or the vertical breaking route will be open. Zone coverages like Cover 2 or Cover 3 that ask the corner to sink deep and the linebacker to cover the flat are vulnerable here since the swing attacks the void underneath before the linebacker can react. Man coverage with no underneath help against the HB can be exposed instantly since the swing creates immediate separation against most linebackers and safeties in man matchups. Watch for a user controlled defender lurking in the shallow flat or spying the HB, this is the primary counter to this concept and forces the quarterback to progress to the out and up route instead. Disciplined zone defenses that keep a linebacker or nickel corner squatting at five to seven yards can take away both levels of this concept, forcing a checkdown or scramble if the pass rush also holds contain.
Use pre-snap motion or alignment reads to confirm whether the defense is showing man or zone before the snap, since this concept thrives against zone shells that leave flat defenders with soft outside responsibility.
Hot route the HB swing to a flat or shoot route if you see a nano blitz or overload pressure look, since the swing is your answer against aggressive edge rushers and blitzing linebackers.
Pair this play with Mtn Snag Curls or RPO Zone Snag in the same set to keep the defense guessing between quick horizontal stretch concepts and curl or snag combinations that attack the same underneath zones.
Best called on early downs or third and short to medium distance since the swing route provides a safe high percentage completion while the out and up route offers a chunk play if linebackers bite on the swing action.
Watch the flat defender's depth at the snap, if he sits inside expect the swing to have a clean release, if he widens quickly be ready to climb to the second read up the sideline.