I came back for a teaser during the Super Bowl week promising a more regular return to blogging. Unfortunately, other things got in the way, but I've also been diving deep into the 2014 film to put together a rather large project to get us through the first half of the offseason. Last year I dove into the scheme and execution behind the Eagles Top 25 plays of Chip Kelly's rookie season with the Eagles. That was a fun project and we might get to it again this offseason, but first with the help of 2 full seasons of Chip Kelly's offense on tape, I wanted to try and put together a more definitive overview of the Chip Kelly Philadelphia Eagles offense. So over the course of the next few weeks (months?) we'll be taking a deep dive into the philosophy behind Chip's offense as well as how it has evolved from Oregon, to his first year with Philadelphia, and through his second year. What works, what doesn't, where we need personnel, and who that personnel might be? Finally, we'll even add some predictions/recommendations for the future based on what else is happening in the college football and NFL world. To be perfectly honest, there's a lot of content to come out and I really don't have a clear vision how I am going to lay all this out in a comprehensive way, but I'll do my best.
We're going to start the series by taking a deep look into the Eagles run game. Quite honestly, the Eagles run offense is quite simple on the surface. We basically run 4 plays. Inside zone, outside zone, sweep and power. That's it. However, Chip does a nice job of dressing things up in different ways and also incorporating the read-option that has lead to one of the more productive rushing attacks in the NFL the last two years.
I want to kick off this series with a post that addresses one of the more controversial aspects of Chip's run game philosophy. It's something that has bothered some Eagles fans, as well as players over the last 2 seasons.
Why Shotgun?
One of the basic formation elements and philosophies that Chip Kelly has taken to the Eagles from his days in college football is running often out of a Shotgun formation. While it is catching on more and more in the NFL, most people seem to prefer the more traditional lining the QB under center in the I-formation with a lead-blocking fullback. However, if you do a bit of channel surfing on a Saturday afternoon during college football season, you'll see the vast majority of offenses being run out of the Shotgun. Why?
For the answer I'll go to 2 of the best football writers in the country in my opinion in Chris Brown from Smart Football and Ross Fulton from Eleven Warriors. In this terrific post Ross, with the help of Chris, explain why teams base running games out of the shotgun in a spread offense. Here's a key excerpt:
For my purposes, I will define spread as any offense that is based out of shotgun to run the football.
The definition itself somewhat belies the answer to my question. The short answer to why a team wants their quarterback in the shotgun is arithmetic. As Chris Brown of Smart Football succinctlydescribes, both the offense and defense have eleven players. The defense will always outnumber the offense, however, because the defense has a counterpart to the offense's ball carrier, and thus an unblocked defender.
A pro-style offense handles this by using the passing game as a threat. That unblocked defender generally has to play deep as a free safety to defend against the pass. However, from a pro-style system, once the quarterback hands off the defense now has two unblocked players, because the quarterback becomes a spectator, leaving the defense's counterpart to the running back and quarterback both free. As a result, the defense not only has an unblocked free safety, but also a defender closer to the line of scrimmage, generally in the form of the unblocked edge player away from the called run.
It's a great explanation and should clear things up. Let's take a look at a few examples to illustrate the point a bit more clearly.
First let's go back in time a bit to the Andy Reid regime and have a look at an inside zone play against the Bucs. As shown below the Eagles have 6 blockers for the run. The Bucs currently have 6 defenders in the box. This is 6-on-6 and is a favorable running situation. However, the blocking scheme will not account for the 7th run defender who shortly comes on the screen from the safety position based on the DL alignment and stacking of the LBs.
The Eagles block it well up front but you can see the safety coming in unblocked to stuff the play for a loss:
One of the main issues here, is that the Eagles have to block the edge defenders with their RT and TE. Because the RG is covered on this play he needs to correctly release to the second level to get the LB. However, no one is left to account for the safety.
In contrast, let's look at an inside zone play run from the shotgun with the read-option. The Eagles have a 6 man line meaning they have 6 blockers for the run on this play. The Jaguars will have 7 defenders as the safety moves up in run support to be the force defender protecting the weakside alley and bubble (more on that later). Now that Foles is in the Shotgun and facing the play, he can read the edge defender (#6) and essentially block him. Note this was not possible in the above play because Foles was under center and is turning his back on the defense.
You see here that Ertz gives his man a little shove, but his assignment is to block to the playside left and get on defender #5 at the second-level. The edge defender #6 is frozen and unblocked on the play. With Foles essentially freezing the edge defender on the backside, the Eagles re-gain their numbers advantage. Essentially they have 6 blockers blocking 5 defenders on this play. What makes this play worse for the Jaguars is the safety has motioned out of position because of force and bubble responsibilities. As a result, Sproles finds the room for a 49 yard TD.
Let's take this a step further and see how it impacts the horizontal stretch plays and sweeps the Eagles like to run. Again, back to the Andy Reid era. This is going to be outside zone to the left and we're going to monitor the weakside edge defender highlighted in red. Foles is under center in the I formation.
After the snap, check out the edge defender crashes hard down on the play and chases immediately. One way pro-style offenses try and keep this edge defender honest is with the bootleg action and pass downfield. It's a good approach but has it's downfalls, most namely the QB turns his back on the defense, can't read where the defender and might walk into immediate pressure if that DE keeps contain. However, here you can see the DE doesn't have much respect for Foles' and crashes down the line:
And that unblocked defender ends up being the guy who ultimately makes the tackle on Brown behind the line of scrimmage.
What hurts this even more is that this was the Eagles run-heavy formation. They had blocking TE Clay Harbor on the line and used a fullback. They basically dedicated 7 blockers on this play, and it ended up in a loss.
Let's flip back to the modern day. Here are two quick shots of plays against the Texans. These are sweep plays instead of outside zone, but the point remains. Look how much Sanchez's read holds the edge defender in these two shots. As a result, the Eagles gain the arithmetic numbers advantage on the play-side of the sweep in both cases for big gains:
The Eagles gained that advantage my blocking with the QB! Not an extra TE or a FB. Of course this has a downstream impact on the passing game. If they can block 7 defenders with 5 OL and a TE, it allows them to deploy 3 receivers in the passing game. This is important for my last point about Shotgun. As we've mentioned many times here before, the read-option is not just for the running game. Many coaches including Chip Kelly have implemented what we call "packaged plays" that provide a run/pass option based on key read from a defender. By lining up in the Shotgun, this gives the offense perhaps it's most powerful weapon, the option for a post-snap read to decide whether the offense should run or pass. I referenced the bootleg action above. The other issue with that is it is a pre-snap decision. The QB needs to call that play that will require him to hold the ball and bootleg. Because his back is turned to the defense, the decision is premeditated. Basically, the QB can't adjust depending on whether the DE crashes or plays contain, the play call is the play for better or worse.
Alternatively, lining the QB in Shotgun allows them to read a defender and make a post-snap choice where the defense is always wrong (in theory). We'll get into packaged plays and this idea a bit later in this series, but I'll finish with one more example to illustrate the point. This play is not a packaged play, but the advantage is that Sanchez never has to turn his back to the defense and thus can get to his read, and his passing target quicker.
The blocking on this play looks like outside zone run action. But it's essentially a bootleg. Sanchez, never has to turn his back on the defense and can watch his routes develop:
Cowboys linebackers bite on the playaction fake, and Sanchez is going to hit a wide open Jordan Matthews over the middle of the field:
This same play is probably there if Sanchez runs it under center off of bootleg action, but perhaps it takes a little longer to develop and potentially increasing the likelihood of QB pressure of LB recovery in coverage.
To finish, I am not suggesting that running out of the shotgun is without it's flaws. There are certainly issues with it that have forced Chip to evolve and change and we will get to those in due time later in the series. I just wanted to start off by explaining the reasoning behind one of Chip's core philosophies.
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