Football Fundamentals: I-Formation RB Isolation Run Plays

This is a series post with lots of play diagrams. Where it lacks depth, it hopefully makes up for with breadth. The goal of this post is to demonstrate the many run game nuances that are at your disposal, outside the very basics that you can find almost anywhere. I will point out some key attributes for the plays, but for the most part the diagrams will stand alone outside a brief description. This post is limited (out of necessity) to strongside plays that are given directly to the RB. It does not include FB runs, or QB runs, or H-Back, Wing, TE, or WR runs. It also doesn't include option plays. Those are things for future posts.

Why did I select an I-formation, which is mostly going out of fashion, and how do I expect this information to be utilized? The I-Formation is a classic 2-back set that, by the time it was implemented, had the benefit of a lot of football history. It is also a highly adaptable run formation, along for offsets, for H-backs, and other aspects that allow essentially any run concept to be incorporated into its framework. And that's the important bit: you can look at an I-Formation run play and easily carry it forward to many modern formations. For instance, by altering footwork and possibly timing, any of these plays can be utilized in the following:

  • 2-Back Shotgun Runs (with the second back potentially being a FB, an H-Back, a Wing, or a Sniffer)
  • 1-Back Shotgun QB Runs (utilizing the RB as an added blocker)
  • 1-Back Shotgun Read Options (the read of a run-run option, run-pass option, or pass-run option take the place of the additional blocker).
Many of the best current offenses often circle back to old formations. In the NFL, along with the modern spread concepts, you see a lot of the best offenses utilizing Wing T concepts. This set of plays does the same where it can (though, again, recognize that the option packages and fake packages are not included in this post, so it is somewhat limited). Below, you will see each play blocked against the two fundamental Even Fronts (4-3 Over and Under).

Let's start with Isolation Plays

Isolation Plays

This is the basic Iso play, which I've detailed here. ID the MIKE, block him with the FB, and get downhill.

Double Iso
This play is like the Iso, but utilizes a second lead blocker. If there is an unaccounted for overhang defender, the added iso blocker with ID him and make that block.

Insert Iso
Typically known as a shotgun run play, the insert iso with see the playside lead blocker account for the playside LB, regardless of defensive formation. This allows the second lead blocker to take a different path to the next LB to the backside of the formation.

Swapping roles of the Off-Y TE and the FB provides some backfield cross flow which can cause the LB level to freeze as it attempts to read the play. 

Another isolation play, but here the FB is going to take a backside LB rather than a playside LB. This altered path can cause the LB level to hesitate, allowing for extended doubles at the point of attack and/or greater spacing between levels.

Fan Iso
This run play incorporates fan blocking on the front side (i.e. block the gap outside). In this way, it limits double teams, but ensures you remain gap sound and allows the OL to get immediately out to the second level. Often times this play will cut back, as the FB runs through the primary hole, but has blocking responsibility on the backside LB.

Bear Iso
Created as a counter to a Bear defense, a Bear Iso is a standard Iso with an added fold block rather than a double to the backside LB.

Take an Iso play and kick it one gap further playside and you get a Lead Play

Double Lead
Just like the Double Iso, you are adding a lead blocker through the run hole. But again, if there is an unaccounted for edge player that could potentially cut into the back field, the blocker must account for him.

Midline Seal-Out
Based on the midline option play, the idea here is that you are effectively all working toward sealing out the playside A gap. This means extended doubles in the middle that tend to work vertical into the lap of the LBs. Added initial flow playside can help influence the LBs to treat it like Duo.

Crack Boss
The "Isolation" player here is the safety, as the FB will be eying him with his block. In order to do that, one of the most effective ways is to have a crack block from the edge. Why force LBs and Safeties make tackles when you can force a CB.

* Note, all nomenclature is my own, though attempts to be fairly consistent with standard. As plays get added, you can add "tags" to base plays (as I have done) or create single word names to take the place for shorter communication.