Playbooks

PA Sprint HB Flat is a play-action sprint out pass from Singleback Bunch that sells the run fake before rolling the quarterback outside the pocket. Off the bunch alignment, one receiver runs a deep corner route while a second climbs a vertical seam behind it, the HB releases into the flat to the boot side as the checkdown, and the backside X runs a shallow drag underneath. This is a man beater on the flats and seam combo, giving the quarterback a boot pocket with a quick flat option, a seam option to attack linebacker overlap, and a deep corner shot if the safety bites on the run action, so the primary progression is flat to seam to corner.
Watch the flat defender at the snap, if he sits and reads the quarterback's shoulders instead of widening with the HB release, jump the flat route for a pick six opportunity. Key the play side linebacker's run fit, if he bites hard on the play fake and vacates his zone drop, the seam route behind him will be wide open. Identify single high versus two high safety shells before the snap, two high alignments cut off the deep corner route and force the quarterback to work underneath. Spy or blitz the boot side edge to disrupt the sprint out timing, since the quarterback needs a clean pocket to climb through his progression from flat to seam to corner. User a linebacker to lurk the shallow drag on the backside, this route sits in a soft spot of most zone drops and is a common checkdown when the boot side is covered.
Use this on early downs like first or second and short to medium distance so the run fake actually holds linebackers and safeties.
Check the safety depth pre-snap, if you see a single high safety cheating up to respect the run, the corner route behind it has a strong shot at a big play.
Hot route the backside drag into a deeper crosser or spot route against zone shells if you need a more reliable underdisiciplined-defender beater.
Pair this with HB Draw and Inside Zone Split from the same set so defenses respect the run fake and stay honest on early downs before you hit them with the boot.
Against aggressive man coverage defenses, prioritize the flat to HB since the sprint action naturally creates space for the outlet before the seam and corner develop.