Playbooks
Quick Under is a quick-timing zone beater out of the Trips X Nasty Offset WK set that gets the ball out of your hands before pass rush and coverage rotation can develop. The trips side runs a shallow under/drag combo with a corner or curl route stacked behind it to hold linebackers and safeties, while the backside X works an isolation route to punish man coverage or soft corners. The primary read starts with the under route crossing the formation, and if the flat or hook defender widens with it, you progress to the backside isolation route for the man beater window, checking down to the aligned back as your last resort against a hard blitz.
Watch the flat defender and the hook or curl linebacker pre-snap, if they are sitting at a shallow depth with outside leverage they can undercut the under route and jump the throwing lane. Check for two high safeties versus single high, Cover 3 with a hard flat corner squeezes the under route hard and forces you to the backside isolation route for the conversion. Look for a Mike linebacker showing blitz depth or crashing the A gap presnap, this often means the underneath zone drop will be thin and the shallow crosser can be a home run against man coverage. Post-snap, track the user controlled defender if they are dropping into a lurk spot over the under route, this is a common way to bait quarterbacks into a pick six, so be ready to check down immediately. Against Cover 0 or all out blitz packages this play gets exposed quickly since there is no safety help over the top, so lean on the hot routed backside isolation route for a fast release before pressure arrives.
Call this on early downs or third and short when you want a high percentage completion without exposing yourself to a sack on a longer developing route.
Identify the coverage shell pre-snap by checking safety depth, if you see two deep safeties sitting at 12 plus yards you are likely against Cover 2 or Cover 4 and the under route sits in the soft spot underneath.
Hot route the backside X into a slant or quick out if the corner is playing off coverage to speed up the timing against zone drops.
Pair this with Mtn Triple Slants and Quick Short Post from the same set to keep the defense honest on quick game reads, forcing linebackers to respect multiple crossing patterns before they can sit on the under route.
Use play action counters like Sft PA Curl Seam later in a series after establishing Quick Under to bait linebackers into jumping the shallow crossers, opening up the deeper seam shot.