The inside zone is the foundation play in Chip Kelly's run offense. In 2013, the Eagles tore defenses up on the ground primarily with Lesean McCoy using this play. Naturally, over the course of the last 2 seasons, defenses have schemed and experimented with different ways to defend the play.
Fortunately for the NFL defenses that have faced the Eagles in 2013 and 2014, they've only had to deal with a mobile QB when Michael Vick was starting. Since Vick got injured, Nick Foles, Matt Barkley and Mark Sanchez have run the Eagles offense. Adding the read-option component to the inside zone makes it an even more dangerous play, but the Eagles haven't really had that dynamic since October 2013. As a result, since we didn't have a mobile QB in 2014, we aren't going to talk much about the read-option on this post. Chris Brown did a terrific piece for Grantland a few years back that highlights some of the ways defenses have schemed to stop the read-option. Excellent reading.
Instead, we are going to focus on the schemes and tactics that teams used to slow down our inside zone running game.
The best and easiest way to defeat the inside zone run game is with great players. The inside zone is designed to attack the interior of a defensive line and therefore, if you can get a dominant interior defensive line it should help you defend the inside zone running game without having to build in too much scheme. Of course, there is a reason why interior DL (DT in 4-3 or DE in a 3-4) are so coveted. Truly disruptive players that play this position are quite rare and thus have a lot of value associated with them. Here's a couple of examples how great individual efforts along the DL can wreak havoc on the inside zone running game. One of the things we mentioned in previous posts is that, in general, the inside zone formation dictates the playside to the defense. As a result, teams can line up their best players over the A and B gaps where the inside zone run is most likely to hit.
Let's take a look at the first example which is a mix of a great play from Rookie of the Year, Aaron Donald and a missed assignment from C, David Molk. In the shot below, you will see Aaron Donald will use his excellent explosion to attack the A gap off the snap. In yellow, you see the blocking assignments for the Eagles OL on the inside zone. The problem on this play is two-fold. Donald is an elite penetrator and he will hit that A gap immediately.
The second problem is that David Molk misses his assignment. On this play the MIKE LB is lined over the backside and thus Molk is not covered. He will be Todd Herreman's responsibility on a peel block. It is Molk's job to help double team Aaron Donald and take away that A gap penetration. Instead, you see Molk immediately release to the second-level and Donald explodes through the A gap and gets into the backfield immediately. Tobin has no chance against Donald:
Here's another example against the Texans' JJ Watt. The key blocks here are highlighted in yellow. Herremans and Johnson will initially double JJ Watt and then Johnson will peel off to the second-level LB:
After the snap this looks like it might be a good example of picture perfect execution as I highlighted back in Part 5 of the series. Herremans and Johnson get a good double team on Watt and Johnson is getting ready to leak to the second-level:
He'll leave Watt for Herremans and move to the next level. Looks good doesn't it?
but Watt absolutely destroys Herremans once he's left alone and completely disrupts this play in the backfield:
Through the course of this series, you can see how important strong OG play is to success of this play. Late last week we saw that the Eagles released Todd Herremans. It is something that will become more evident as I continue through this series, but even before the release of Herremans I was of the belief that the Eagles would need to make a big splash at this position at some point in the offseason. Herremans' release only makes this all the more likely.
One of the biggest keys to slowing the inside zone run game from a schematic point of view is with the use of defensive line stunts to mess up zone blocking assignments. By now you will have understood how zone blocking works and how an OL knows who he is responsible to block pre-snap. The defense can counter this strategy by confusing the OL with a variety of pre-snap movements and stunts. In 2013, the New York Giants gave us a great illustration of how the "nut stunt" could be employed to mess with the Eagles zone blocking:
Slowing things down, check out the Eagles OL blocking assignments pre-snap. This looks like a very favorable defensive front for the Eagles inside zone play:
The key player to watch is Giants defender #95, Shaun Rogers. As Kelce releases to block Rogers, he tricks Kelce by stunting around and attacking the back-side A gap. Kelce completely whiffs on the play and consider your zone blocking all messed up. Rogers path of attack will also mess up Herremans ability to peel off the double team. The other key aspect of this play is you'll see #99 and #52 flow to the playside to protect that A and B playside gaps that Rogers vacated:
Pretty sound defensive strategy from the Giants as McCoy is dropped for a loss:
Same idea here from the Indianapolis Colts defense:
Again Kelce gets caught out of position
The Colts are in the backfield forcing McCoy to cutback into the waiting arms of a well-positioned force defender fill:
The Eagles have seen other pre-snap adjustments from the defense such as last minute D-line shifts to try and confuse the Eagles zone blocking tactics. Something like below. Here the Eagles are lining up the QB under center and thus are not dictating the playside. Sometimes the QB can assign the playside based on the DL front he sees. Here, the Packers line up initially, and then at the last minute swap their interior DL into different techniques. This is a risky proposition however against the Eagles tempo as it can lead to the defenders being out of position:
These interior DL strategies and stunts are an effective way to confuse the blocking assignments for inside zone. However, when the Eagles faced the Giants for the first meeting this year, Chip came up with the perfect counter attack. While the Giants focused on stuffing the middle with stunts and shifts, Chip chose to attack on the outside with their sweep play and completely bull-dozed the Giants.
A similar concept to the plays described above is the usage of gap exchanges to mess with the zone blocking up front. We've talked a lot about the scrape exchange in defending the zone read, and this is the same concept instead it is more focused at attacking the running back in the inside zone. Here's a couple of examples. When we played the Rams last year, they were hell bent on attacking the A gap against our inside zone running game. However, they were not careless about it. Generally, when they sent a LB to attack that A gap, they had a LB or safety fill in the abandoned gap to execute the gap exchange. Here, as #55 attacks the A gap to blow up the inside zone at the mesh, LB #58 will rotate over to cover the playside B gap:
McCoy is able to dodge the run blitz:
But has a LB waiting in the B gap. Perfect execution by the Rams:
Here against the Seahawks, the Eagles OL is unbalanced but believes they have their blocking assignments sorted out (in yellow):
But just before the snap, Michael Bennett who is originally lined up wide...creeps into the middle just before the snap and attacks the B gap on the playside. As you can see, this disrupts the Eagles zone blocking.
More importantly for the Seahawks is they have Kam Chancellor coming down to protect the playside C gap that Bennett just vacated. Good sound defense from the Seahawks and another negative play for the Eagles.
Last example, is one where the defense cheats a little. Because the Eagles run inside zone so much, the defense knows the responsibilities of the OL probably just as well as the Eagles OL know themselves. Here are a couple of examples of how the DL will hold the peel blocker to prevent him from getting to the second-level. Here against the Texans you will see the blocking assignments for Kelce and Mathis. They will initially double the NT and Kelce will want to peel off onto the MIKE LB.
But the NT knows this, so he holds Kelce and prevents him from getting to the second level:
This frees the LB to flow to the ball untouched and fill the hole for a run stop:
One more example against the Seahawks. Here, #99 will attack the inside shoulder of Evan Mathis:
Based on the angle he takes it's very difficult for Mathis to peel off to the 2nd level and #99 sneaks in with a little hold for good measure to keep Mathis from peeling off to Bobby Wagner:
As a result, Wagner remains clean and is able to fill the hole and make the tackle short of the goalline.
You sometimes see a rare flag for defensive holding on the DL but it is most commonly called on a screen play where the DL holds an offensive lineman to prevent him from getting downfield on a block. This one is tougher to catch because it is in the trenches, but it happens nonetheless.
Next up, we'll talk about some of the ways Chip has altered his schemes to counter some of the methods highlighted above to slow down the Eagles inside zone game.