Playbooks
Midline Read Iso is a triple option run play out of the Flexbone Normal set that puts the quarterback on a midline dive read against the interior defensive line while the fullback leads through the hole as an isolation blocker on the play side linebacker. This is a pure run play built to attack the numbers game up front, not a play-action or RPO concept, and the blocking scheme pulls the guard away from the dive read while the fullback isos the second level defender. The primary read progression starts with the quarterback reading the first down defensive lineman inside the tackle box: give to the dive back if that defender crashes inside, keep and follow the fullback iso block if he stays home or slants outside.
Watch the alignment of the interior defensive line pre-snap, a 2i or 3 technique shaded toward the play side dive lane signals the defense is selling out to stop the dive phase. Key the play side linebacker depth after the snap, a linebacker sitting shallow and square is reading the fullback iso block and will try to spill it outside rather than take it on. Identify if the defense is running a scrape exchange with the defensive end and linebacker, this is the primary counter to midline option and forces the quarterback to make a faster keep decision. Look for user controlled defenders flowing hard downhill pre-snap, an aggressive crash from a user player at the mesh point usually means they are gambling on the dive and leaving the perimeter light for the quarterback keep. This play struggles against disciplined even fronts with two gap defensive tackles who read and squeeze rather than attack a gap, since it removes the clean dive read the quarterback needs.
Use this play against defenses that load the box with four or more defenders since the midline dive naturally creates a numbers advantage away from the dive read key. Check pre-snap for a shaded nose tackle or 3 technique that crashes hard on run downs, since a disciplined read defender who sits still forces the quarterback keep and lets the fullback iso block clean up the linebacker. Pair this call with Midline Triple and Inside Veer Triple Opt in the same set so the defense cannot key on a single dive read technique, forcing linebackers to hesitate on every snap. Run this on early downs, especially first and second and short to medium, when defenses are still base personnel and have not sold out with extra DBs to stop the option game. If the user controls the read defender and consistently sits to take away both options, hot route the fullback to a quick lead block angle or motion the slot back pre-snap to adjust the numbers before the snap.