Playbooks

Backs Cross out of Shotgun Split Y Off (21 personnel) sends both backs on a crossing pattern underneath while the receivers clear out the deep and intermediate zones. The outside receiver runs a deep corner up the sideline, the slot works a deep dig across the middle, and the tight end pushes vertically up the seam to hold the safety, while the two backs cross each other in the shallow zone, one running to the left flat and one to the right flat off the initial mesh. This is a man beater built off natural rub concepts from the backfield cross, with the primary read progressing from the shallow crossers underneath to the deep dig and corner route if the crossers get picked up in man coverage.
Look at the alignment of the linebackers and nickel defender before the snap, if they are pressed up on the backs in the backfield expect man coverage and the crossers will have a rub advantage. Watch for a user controlled linebacker or safety spying the shallow cross, since a good lurk defender can undercut both backs and blow up the primary read. Check the safety depth at the snap, a single high safety struggles to get width to help on the deep dig, so favor that route against Cover 1 or Cover 3 looks. Against Cover 2 or Cover 4 shells, the deep corner route from the outside receiver can be taken away by a flat footed corner playing the deep quarter, so be ready to reset to the crossers underneath. Blitz packages that bring extra rushers off the edge attack the quarterback quickly since both backs release into routes instead of staying in to block, so account for hot route adjustments or a quick check down if you see overload pressure pre-snap.
Use this play in obvious passing downs like second or third and medium where defenses are more likely to play man coverage on the backs. Read the crossing backs first since the natural rub at the mesh point creates instant separation against man defenders, especially if you diagnose man coverage pre-snap by checking if defenders are lined up over the backs instead of sitting in zone drops. If the defense shows zone shells like Cover 3 or Cover 4, work your eyes to the deep dig route sitting in the hole between the linebackers and the deep safeties. Motion one of the backs before the snap to confirm man versus zone, if the defender follows the motion across the formation you know it is man coverage and the crosser should win immediately. Pair this play with Wheel Trail or H Choice from the same set to keep defenses honest, since both plays start with similar backfield action but attack different levels of the field, forcing linebackers to hesitate on their crossing route reads.