Playbooks

RPO Zone Read Bubble out of Bunch Str Nasty gives the QB an inside zone run read paired with a bubble screen to the bunch alignment. The diagram shows the bunch receivers releasing outward with the nearest slot man sitting into a bubble route while the running back takes the zone handoff path behind the line. This is a true run pass option, so the QB is reading the flow of an underneath defender (typically the alley defender or nearest linebacker to the bunch) to decide between handing off the zone run or pulling and throwing the bubble. Primary read progression is defender near the bunch first: if he crashes down on the run, throw the bubble immediately, if he sits or bails to cover the bubble, hand off the zone run.
Watch the alignment of the defender closest to the bunch formation presnap, if he is stacked in the box expecting run, that is a bubble throw look. Post snap, key on whether that defender steps up to fill the run gap or shuffles laterally to cover the bubble route, his first movement tells you the correct RPO decision. This play beats aggressive run blitzes and linebacker heavy fronts that crash downhill, since the bubble screen punishes defenders selling out on the zone run. Zone coverages with disciplined linebackers who stay patient and read the mesh point can shut this down, forcing you into a low value handoff into a stacked box. Man coverage with off ball linebackers spying the backfield can also disrupt the timing, since a quick blitzing linebacker can beat the bubble throw before it develops.
Presnap, identify whether the defense is showing a run blitz or a light box, since a stacked box with the alley defender crashing hard is your green light to throw the bubble instantly.
Use the hot route to check the backside if the defense shows heavy pressure from the bunch side, but in most reps you want to trust the design read and get the ball out fast on the bubble against overloaded fronts.
Against soft or passive linebacker play where the alley defender sits back in zone, take the free inside zone run and let your line work double teams up front.
Pair this with Inside Zone from the same set to condition the defense to respect the run, then come back to RPO Zone Read Bubble or RPO Zone Peek later in the drive once linebackers start cheating downhill.
This play is best on early downs (1st and 10, 2nd and short) where defenses are more likely to sell out against the run, giving you an easy bubble throw for a manageable gain.