JERSEY CALLS: A Jersey call is when the “dive key defender” (#1 in your count) is blocked by the play side OT.
This may or may not be actually “called” by the O-Line prior to the snap. At times, the O-Coordinator may signal in that he wants that dive key defender blocked by the OT in order to ensure a double option occurs instead of a triple option play. The diagram above shows two instances when a jersey call is made. These two jersey calls are made “on the run” while the final diagram shows no jersey call whatsoever. “Jersey on the run” simply implies that prior to the snap of the ball, no official jersey call is made either in the huddle or at the LOS. What happens instead, is as the play progresses, that dive key defender is indeed blocked by the play side OT.
Diagram #1: This is the “EZ Stunt; Jersey on the Run”. An EZ stunt is when the defense attempts to confuse the QB by having the DE and OLB “switch” assignments”. In this case, the LB slants inside to take the B-back while the DE keeps contain on the QB. On many occasions, even though both these defenders are supposed to be unblocked (since the DE is our Dive Key while the OLB is the pitch key), if this stunt does occur, our Veer Releasing OT will in all likelihood, “run into” the OLB and therefore this play becomes a “jersey on the run” as the OLB is being blocked by our OT. In this case, the OLB has now become our Dive Key (even though he is blocked) while the DE becomes our Pitch Key. Our rule of thumb on any Jersey Call is as follows: if the Dive Key defender is ever blocked by our OT, the QB will automatically “pull” the football from the gut of the B-back and instead, option the DE on a double option play.
Diagram #2: There is no EZ Stunt happening here as the DE becomes our Dive Key defender while the OLB is our pitch key. However, if that DE charges hard right into our Veer Releasing OT, this play becomes an automatic jersey call (since the Dive Key is being blocked). The play once again becomes a double option to the perimeter.
Diagram #3: This diagram shows what normally happens during our triple option play. Prior to the snap, our QB has determined that his Dive Key is the DE while his Pitch Key is the OLB. Our OT is able to Veer Release to get to the 2nd level Mike LB. There is no Jersey Call on this play as the Dive Key has not been blocked by the OT.