Playbooks
Quick Reference
Breakdown
Mtn Double Under is a route-based passing concept out of Shotgun U Off Stack with 12 personnel and a pre-snap motion tag. Off the stack alignment, the two outside receivers push vertical seams up the numbers while the stacked receiver runs a deep dig that settles behind the underneath crossers, and the two inside receivers run shallow under routes across the middle of the field creating a natural rub against man coverage. This is primarily a man beater thanks to the crossing under routes clearing traffic for the dig, though the double vertical stems on the outside give it zone beater value against soft shells by stretching the deep safeties. The primary progression starts with the two verticals on the outside to see if a corner blitz or press look opens a big play, then works to the dig sitting down in the middle read, and finally checks down to the shallow under crossers for a safety valve.
Defensive Reads
Pre-snap, check safety depth and count defenders in the box, since a two-high shell with no extra rusher tells you the dig route to the stack side will have a soft landing spot. Watch corner alignment on the outside receivers, since press man alignment signals the double vertical routes have one-on-one win potential against a user-controlled corner. Post-snap, track any linebacker or nickel defender sinking into the shallow crosser lanes, since a lurking defender there can jump the under routes and create a turnover if you force that throw. This concept struggles against zone blitz packages that drop a defensive lineman into the shallow zone, since that extra body clogs the crossing routes and forces you into the deep dig or verticals. Cover 3 with a hard flat defender can undercut the under routes, so if you see the cornerback sink into the shallow zone at the snap, work the dig or the vertical on the opposite side instead.
Usage Tips
Use the pre-snap motion to identify man versus zone before the snap by watching if a defender follows the motion man across the formation.
If the defense shows single high safety, prioritize the two outside vertical routes since the corners likely have no deep help.
Against man coverage, let the underneath crossers develop fully to pick off trailing defenders and free the dig route sitting in the intermediate window.
This play works best on second or third down between 5 and 12 yards, since the dig and under routes give you multiple completion windows short of the sticks.
Pair this with Mtn PA Crossers or Mtn PA Y-Leak in your play-calling sequence, since both plays attack similar crossing concepts and force the defense to respect the shallow game before you hit them with the play-action shot.
