One of the interesting things about football strategy is that even among the most basic plays, there are often wildly different ways to coach them.  To give you a bit of that flavor, I’ve asked other writers to occasionally provide guest posts to the blog.  Most of these guest writers have coached or played in Nebraska, though I’m always open to contributors from beyond the Good Life.  

Today’s guest post is part of a series dedicated to the inside zone play.  We’ve covered this play in the abstract, but for you guys and girls who really want to know the nuts and bolts of it, I wanted to dive a little bit deeper into the blocking scheme itself.  Enter guest poster Ryan Reuter, a Gretna Dragon who was stuck with me for most of this year’s Big Red Coaches Clinic.  After the jump, Ryan breaks down the basics of the inside zone play.  You can harass him on Twitter @Hoss_Reuter if you want more information.

Inside Zone: Flexibility and Power in One

The inside zone (IZ) blocking scheme provides an offense with an answer for multiple fronts, stunts, and blitzes that a defense may throw at an offense.  The blocking scheme is predicated upon technique and execution more than the X’s and O’s that can be drawn up on the whiteboard.  Because of this scheme being something that you can build your entire offense around, there is a decrease in the mental stress on offensive linemen by eliminating the necessity for other techniques and schemes to counter what the defense is presenting.

Under Mike Riley and Danny Langsdorf, Nebraska builds its run game around this scheme.  Although some Husker fans believe that the inside zone blocking scheme is [insert pejorative here], it is actually a physical scheme that is built upon out-muscling a defender at the point of attack and vertically displacing the defender off of the line of scrimmage. However, this is not the first time that Nebraska has used the inside zone blocking scheme, as the scheme held a prominent place in the Husker playbook of the 1990’s.  

Blocking Rules

Who to block in the IZ is predicated upon whether an offensive linemen (OLM) is covered or uncovered by a down defensive linemen (DLM).  Being covered is defined as an OLM having a DLM lined up somewhere within his shoulder-to-shoulder framework.  With this in mind, there are three ways that an OLM can be covered: playside shade, head-up alignment, and backside shade.  

Each of these scenarios presents a slightly different way for the OLM to block the defender.  As a general rule of thumb, offensive line coaches utilize the 90/50/10 rule for zone blocking and helping the OLM reduce any unnecessary thinking at the line of scrimmage:

(1) If the OLM has a defender lined up on his playside shoulder there is a 90% chance that the playside shade will be who the OLM blocks on the play.  

(2) If the OLM is covered by a defender who is lined up nose to nose in a head-up alignment, there are two ways that the defender can slant, so the probability of this being who the OLM blocks goes down to 50%.  

(3) If the OLM has a defender aligned on his backside shoulder, away from the direction of the play, there is only a 10% chance that is this who the OLM will block.  

Below, I have diagrammed how the 90/50/10 rule looks on the field.

Playside Shade

Playside shade:  90% chance that this defender will slant toward the direction of the play and be who the OLM blocks.  If the defender does slant away from the play, it creates an easy blocking angle for our OLM on the right and also the OLM to his inside.

Head-Up Alignment

Head-up alignment:  50% chance the DLM slants toward the direction of the play and becomes who the OLM will block on the play.  This becomes a more difficult situation for the OLM on the right, as the DLM’s movement is less predictable.

Backside Shade

Backside shade: only a 10% that this defender aligned on the backside shoulder of the OLM will slant across the OLM’s face toward the direction of the play.

[Editor’s Note: We can see some of the alignments Ryan references above in the inside zone clip below.  Though this is Inside Zone Slice and not base Inside Zone, notice how the 90/50/10 rule lines up with what the defensive linemen do in this TD play.]

With the different ways that an offensive linemen can be covered by a defender, there are different ways that the OLM will approach blocking this defender off the line of scrimmage, which I will cover in my next write-up.