Before the drill begins, Jeff Stoutland shouts out a two-digit number, signaling the call to his offensive linemen.
He sets up a couple yards behind the line of scrimmage as Jason Kelce prepares to snap the ball, flanked by guards Evan Mathis and Todd Herremans. With 16 offensive linemen in camp, Stoutland is in charge of the largest positional group on the roster. But that can be a good thing on days like this. Before it’s their turn for reps, a couple backups hold orange blocking pads and set up as down defensive linemen. Two more stand behind them imitating linebackers.
It's an 81-degree day in early June, and the Eagles are on the practice fields at the NovaCare Complex working on the blocking scheme for a familiar call: the inside zone. It's a play Stoutland ran frequently at his previous stop, Alabama. And it was Chip Kelly's go-to-work play during his time at Oregon.
When Kelly made the jump to the NFL last year, the inside zone served as the foundation for an offense that set franchise records in yards and points. So there's a good reason why Stoutland yells the same number for the same call over and over again during practice. The pre-snap communication has to be mastered. The footwork has to be flawless. The combination blocks have to be executed. And the second-level linebackers have to be driven down the field with authority.
"It’s something we work on every day," said offensive tackle Lane Johnson. "It’s always gonna be our bread and butter."
Johnson estimated that 40 to 45 percent of practice time for the offensive linemen is rooted in perfecting principles associated with the inside zone. Kelce doesn't think that's an exaggeration.
"I would say yeah, we really spend a lot of time on our double-team blocking with our offensive line coach and trying to make sure that our offensive line is working together," he said. "That’s not really exclusive to that play in particular. We do that on a lot of different plays. But that play, especially against a four-down defense, there’s a lot of the double teams that come around and everything. It’d be hard to put a number on it. But we definitely spend a lot of time on it."
Kelly despises labels. Last year he joked that the Eagles ran the "see-coast offense." If they were to see something they liked that could help them score points, they would run it.
And to a large degree, that was true. It was one of Kelly's biggest strengths in 2013: figuring out what the defense was trying to do and attacking its weaknesses. Some games that meant running more sweeps. Other weeks, the screen game was prolific. And throughout the entire first season, the Eagles did damage downfield, leading the NFL in pass plays of 20+ yards.
But Kelly also believes in having an identity on offense, in addition to the different tools.
"If you give your players something to hang their hats on, they will perform," he said during a Nike Coaches Clinic in 2009. "If they can run the offense with any scenario they may face, you will be successful in running the ball. If they have all the answers to the problems the defense may give them, they will be good."
Given that philosophy, it's no wonder that his offense spends so much time on the inside zone.
"What’s special about the inside zone is that it can hit anywhere," Mathis said. "It’s not necessarily designed to hit in any certain gap. If it’s wide open left tackle to right tackle, it can hit there. The blocking for it is more of a downhill, smash-mouth type blocking and getting on your guys quickly.
"We do it a lot so we get pretty good at it. At first, it took awhile. There’s a few of those blocks on the inside zone that took awhile to get comfortable doing. But over the course of the season, the more repetitions we got, the more we saw it on film, the more we learned the intricacies of the play. Our experience really came to help us."
Boiled down to their simplest terms, the rules for blocking the inside zone depend on whether an offensive lineman is covered or uncovered, as explained by Chris Brown of Smart Football:
If “covered,” there is very little “zoning” at all: The lineman’s job is to block the guy in front of them. Fans, commentators, and even coaches often overcomplicate things. The “zone” aspect comes in with “uncovered” linemen. If “uncovered,” the lineman must step “playside” — i.e. the side the run is going to — and help double-team the defensive linemen along with his “covered” cohort. Once the two of them control that down defensive lineman, one of the offensive linemen slides off to hit a linebacker. It’s not that complicated. Indeed, let’s say the five offensive linemen are covered by five defensive linemen. In that case, each guy (save for maybe the backside offensive tackle) will just block the guy in front of them — there is no “zoning” at all.
Here's an example from Week 3 against the Chiefs:
For TE Brent Celek, RG Herremans, center Kelce and LT Jason Peters, the job is simple: They're covered so they block the guys in front of them.
Johnson, the right tackle, is uncovered so he steps play side and executes a double team with Herremans. Mathis' job changes depending on the depth of No. 55. If that player were farther off the line of scrimmage, Mathis would help on a double team and then move to the second level to get the linebacker. But because No. 55 is creeping up, Mathis goes right for him.
"Sometimes you’re gonna step to a double team and you’re gonna end up not even touching the guy you’re supposed to be double teaming, depending on how he plays," Mathis said. "So at that point in time you have to be able to adjust and get up to the next guy. ...You have to keep your base, you have to keep your balance and you have to adjust to what you see on defense. It’s not just, ‘OK, us two have to start a double team and then block that guy.’ Us two have these two, but it’s only a double team if the guy ends up between us or they play it a certain way. There are a lot of intricacies to this play."
Here, you can see Herremans and Johnson double-teaming N0. 94.
"We are double-teaming a defensive lineman with a mathematical idea behind it," Kelly said at the clinic. "We have four legs, and he has two legs, so we win."
As the play develops, you can see the gaping hole for LeSean McCoy. The next step for the linemen is to get to the second level. This is probably the most challenging part of the play and one of the things the Eagles work on constantly at practice.
"Timing coming off the double teams," Johnson said. "Sometimes if Todd leaves and then I leave to go off to the backer, you leave the down guy unblocked. It’s just a matter of repetition and consistency."
Added Mathis: "On a double team, you’re trying to pretty much take half the man, each of you, and both have your eyes on the second defender who you’re headed to because then that person could fall off on either side of the double team. And that’s where you adjust. One man takes that block, and the other man climbs to the second defender."
Speaking at the coaches clinic, Kelly said he wanted the linemen to be "cheek-to-cheek" on the double team. A key aspect of the play is patience. The linemen never want to leave the combination block early to get to the second level. Kelly's teaching point was that the linebacker should be about an arm's length away. Disengaging from the double team too soon and running to get to a linebacker is a no-no.
And then there's the running back's role. The word that comes up frequently is vision. He reads the movement of the first play-side down lineman and initially aims for the butt of the play-side guard (in this case, Mathis). But the cutbacks are built in. He's just looking for daylight.
"It’s all about his mechanics, making sure he’s doing the same thing over and over and over again," said running backs coach Duce Staley. "As a running back, the most important thing of course is vision. You’ve gotta be able to see what’s going on and you’ve gotta be able to predict what they’re trying to do to you by the front or by the linebackers being plussed or negative, the safety in the box. So there’s so many looks that they can give you that you’ve gotta adjust to along the way.
"If you continue to do something over and over and over again, one of two things are gonna happen: You’re gonna get good at it, or you’ll get run out of town."
McCoy was plenty good at it, setting a franchise record with 1,607 rushing yards, many of which came off of inside zone. Even when the offensive linemen didn't block the play correctly, he was able to elude defenders in the backfield and make something out of nothing.
While the highlight runs frequently show McCoy making opponents look silly in the open field, he first had to get there. Often that meant finding the right crease in between the tackles before getting one-on-one with a linebacker or safety.
"You teach the principle that you don’t ever want to get beat inside," said tight ends coach (and former RBs coach) Ted Williams. "If a defender is going to attack you to your inside shoulder, you need to cover him up and maintain that leverage. If he wants to escape outside, then we’re gonna win that more than we’re gonna lose it because the back’s supposedly not going outside."
Ask Kelly about the inside zone, and he'll tell you that viewing it as one play in a vacuum is a mistake. What makes the general concept attractive is that it allows the offense to get to so many other things. The Eagles still run a read offense, which calls for the quarterback to make decisions and take advantage of specific matchups.
The most obvious variation is the inside zone read. Plenty has been written about this concept in recent years, but the idea is simple: Leave an edge defender unblocked and give the QB the option to keep the ball and run with it.
As you can see, this play is from a true spread formation. The Eagles have their five offensive linemen to account for six defenders in the box. In order for Herremans and Johnson to execute a double team, they have to leave the left defensive end unblocked. The inside zone blocking scheme remains the same, but if the edge defender crashes hard on McCoy, Nick Foles has the option of keeping the ball.
"With an offense like this, you’re running some of the same things over and over again," Staley said. "And being redundant is not bad. ...You just find another way to dress up the pig and continue to move forward."
After Foles had established himself as the starter in the second half of the season, Kelly dressed up the pig differently, utilizing the split zone a lot more.
Here, the Eagles are in a 2-TE set. Instead of Foles reading the edge defender, James Casey comes across the formation and blocks him.
"It depends on how certain teams play the zone, play the read-option and things like that," Mathis said. "If you see a team that crashes that end a lot, then that end can create a problem. So to keep them from being a problem, you can kick ‘em out with a tight end like that.
"It’s still one of our standard zone plays where you just change one man in the blocking scheme."
Added Kelly: "When you pare down your gameplan, what you want to get accomplished, how does it match up with the depth and type of handoff you want to use? How does it match up with the defense that you're [facing]? How quickly do you want the back to hit the hole? Do you want to read people? Do you want to block people? A lot of different combinations in terms of how we're going to do that."
Another variation using a wide receiver in motion:
Again, inside zone blocking rules, but instead of deciding to run with the ball if the handoff isn't available to McCoy, Foles has the option to toss it back to DeSean Jackson.
On these plays, the offensive linemen only need to know that they're blocking inside zone. If the QB decides to take one of his other options, that's on him.
And finally, there are the built-in pass game elements with inside zone.
"It sets up a lot of things," Mathis said. "When you’re doing something so well and you make it look like you’re about to do that thing again, then they bite on that and it opens up so many more things. That’s how football works. You can develop a lot of screens or play-action off your bread and butter play."
Here, the quarterback can hand it off or throw the bubble screen.
And this packaged play features receivers to either side should Foles decide to pull the ball.
"If you spread a receiver to the outside, you must have the ability to throw the ball to him," Kelly said at the clinic. "That is the concept and basis of the spread offense."
In addition to the screens, like every other team in the league, the Eagles use run-action to set up shot plays downfield. The overall premise is simple: Lean on the inside zone. If teams want to take that away, find other ways to do damage.
"There were times in other games where teams were solely trying to stop that play and we were able to get to some other stuff," Kelce said. "We have a lot of plays that can balance with each other. But if you’re gonna leave the middle of the defense open for us to run north and south, we’re gonna take that."
The inside zone is not unique to the Eagles. It's run by teams across the league. But when Kelly and Stoutland took over, there was a learning curve. There was no big announcement about the importance of the play, but as soon as the Eagles started practicing under Kelly, they knew what their foundation was going to be.
"This play really wasn’t in the [previous] playbook," Kelce said. "We had a similar play. It was similar, but it was more of a designed cutback play, rather than a true inside zone. And that really didn’t have much to do with Andy [Reid]. I think that was Howard [Mudd's] techniques when I first got here.
"Howard really was a big fan of outside zone. And we used to run the crap out of that under him. And it was more like you’re running to the sideline. And then we would put in off of that a play that would look similar. But it was a designed bend-back. So you knew where the ball was going. In this situation, in a true inside zone, it can hit either side. It can go anywhere it wants to. That all is indicative on the way the defense plays it."
The one defense that shut down the inside zone better than any other last season was the Giants. In two games against New York, McCoy managed just 94 yards on 35 carries (2.7 YPC). The Giants shaded their nose tackle in between Kelce and the play-side guard. That often created a one-on-one matchup. At times, the nose tackle would shoot upfield; other times, he would angle back across Kelce's face. The "nut stunt" gave the Eagles' center problems all game long.
"It really depends on what front you’re presented with, and not just the front, but how that particular guy or how that team plays blocks," Mathis said. "So I mean you could see the same front, but have certain defensive linemen that do different things and you adjust. You have to prepare for what they’re gonna do."
The goal in the offseason is to continue to come up with solutions so that problems are easier to deal with in 2014.
"If your players have not run that play in a critical situation over a thousand times in practice, you will not have a chance to be successful," Kelly said at the clinic. "With our inside zone play, we get so much practice time and so many reps that we can handle all the other scenarios that come about. Instead of trying to outscheme your opponent, put your players in an environment where they can be successful because they understand exactly what they have to do."
And with that, the Eagles' offensive linemen settle in their stances and get ready to run through it once again.