The jet sweep/inside zone became commonplace despite a team’s offensive scheme because it (1) allows a team’s speed guy to attack the edge of the defense, often with plenty of green grass around him, (2) slows defensive backs’ reads if they become overly aggressive in run support, (3) can take advantage of a strong run blocking offensive line, and (4) has built in constraints when a defense begins to slow down the initial jet sweep.
Here’s just one example (of many on his 2013 highlight reel) of Melvin Gordon taking it to the house.
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Here Wisconsin runs it with Gordon lining up in the slot and the fullback as the lone man in the backfield. Gordon comes in motion and will accept the handoff towards the unbalanced side. The strong side tight end and tackle release to block the edge, but Northwestern’s linebackers move toward the inside zone and don’t come close to reaching Gordon or even his lead blockers.
While spread-to-run offenses read defenders and use options to balance a defense’s numbers advantage, one-back and I-formation teams can use pulling linemen to create their own numbers advantage at the point of attack. In the clip above, the strong side defensive end is left completely unblocked with the tackle and tight end releasing to lead block. When only one outside linebacker flows towards Gordon, the two blockers outnumber the slow to react Northwestern linebacking core. From that point, Gordon simply has to outrun the secondary along the edge.
The jet sweep’s success is predicated on the defense respecting the base inside zone, but it’s also possible to simply give it to the lone back and have the slot man fake the jet sweep as well. This helps constrain defenses that cheat a defender into the alley between the line and corner, or bring safeties up quickly on aggressive run support.
Further, if defenses begin keying on Gordon lining up in the slot, then Wisconsin can easily change personnel. They run the same play and rotate Jared Abbrederis, James White, and Corey Clement with Gordon around the backfield.
The jet sweep/inside zone is also easy to run out of the gun and doesn’t necessarily require the quarterback to run either (direct link here):
As opposed to Wisconsin running it with an unbalanced line and the edge linemen blocking downfield, South Carolina runs a similar play from a balanced set out of the shotgun. This wrinkle looks most similar to Connor Shaw running the inside zone read, except Shaw has the choice instead to give on the jet sweep or on the inside zone (which Davis bounces outside when his line is beaten to a man). Georgia wins the line of scrimmage and aggressively attempts to stop the jet sweep/Shaw keeper, but fails to account for Davis on the opposite edge.
Here, the quarterback read is more important than massing blockers at the point of attack. In either set, read-based or unbalanced with pulling linemen, the offense ideally has the jet sweep-side corner playing man coverage so that his back is turned away from the jet sweep coming his way. If the quarterback can recognize tight man coverage and a single-high safety, then he knows that giving the sweep has a high probability of success.
While designed around a solid foundation, the play isn’t perfect: defenses can disguise their coverage, safeties can move forward in run support, linebackers and nickelbacks can cheat into the alley, and defensive ends can confuse a quarterback’s read.
Of course, that’s when the offense counters once again with the play action jet sweep/inside zone (direct link here):