Chip Kelly offense 101: Passing game, part 2

Yesterday, we looked at some of the ways Chip Kelly’s passing game stretches the defense from sideline to sideline. While those concepts are an important part of any passing game, they make up a relatively small portion of Kelly’s overall aerial attack. Much like Kelly’s run game is more north-south than east-west, his base passing game is more vertical than horizontal.

Vertical stretches, as you might have guessed, attack the defense downfield, from end zone to end zone. Offenses typically accomplish this in one of two ways: 1) high-low reads, which isolate a specific defender with a route in front of and behind him; and 2) 3-level stretches, which overload a section of the coverage with a short, intermediate, and deep route.

Today, we’re going to focus on the first group of vertical stretches in Chip’s passing game, beginning with an old Bill Walsh staple…

Drive

While the routes have been around for a long time, it was Walsh and Jerry Rice that popularized the drive concept. Walsh used it as a way to get his best receiver the ball running full speed across the formation — speed in space. In its modern form, drive remains a versatile part of the passing game, providing options against nearly any coverage type.

Whereas Walsh used this concept to get the ball to an outside receiver, Kelly prefers to run it with stacked receivers in the slot. Much like the mesh concept, drive starts with the shallow cross. But in this case, the shallow cross is paired with a dig route — a deep in-breaking route run in the void between the linebackers and safeties — to create a high-low read for the quarterback in the middle of the field, which he reads short to deep.

"We just have a high-low play going with the tight end running a shallow cross and a dig route over the top of it," Kelly explained on PhiladelphiaEagles.com. "And then if [the defender] is going to double [the dig route], then we think [the shallow] will clear. If he’s going to sit and hold his feet on [the shallow], then we know [the dig] will clear."

Routes run by the outside receivers will change, but will always be some sort of vertical (go, post) or out-breaking route (comeback, deep out), which prevents them from carrying extra defenders into the middle of the field where the primary routes are working. These routes are not part of the normal progression for the quarterback, but can instead act as "alert" routes if the offense has a matchup advantage.

Levels

Peyton Manning has shredded defenses with the levels concept for years, and functionally, it’s almost identical to the drive concept. The primary difference is that the shallow cross route is exchanged for a more deliberate, short in-breaking route.

The quarterback’s progression doesn’t change — he’s reading short (in route) to deep (dig route) to checkdown — nor does the effect on the defense. And while Kelly will run levels from the same look as drive — with stacked receivers on the inside — he also likes to call levels from a more traditional trips look to one side of the formation and a single receiver with an "alert" route on the backside.

"We’re in a trips formation and we have a route combination [levels] over here that we would throw if it’s zone, but we always have an alert on the backside," Kelly explained when breaking down a similar play to the one shown above. "So any time there’s 1-on–1 coverage, [the quarterback] has the ability to go away from the zone side and come back here to the single coverage."

This pairing of a zone beater to one side of the formation and man beater to the other is commonplace in most NFL offenses. For Kelly, in this particular concept, the man beater will often be a corner route from an inline tight end or a wideout with a tight split. Down in the red zone it might change to a fade. But it’s really more about the matchup than any specific route.

Smash

If you paid any attention to the 49ers’ passing game when Jim Harbaugh was in town then you’re familiar with the smash concept, even if you don’t know it yet. Smash was a staple of the Harbaugh passing game, and it doesn’t look to be going anywhere now that Kelly is in town.

The smash concept is a two-man route combination featuring a hitch, or sometimes a short-breaking in route, from the outside receiver and a corner route from an inside receiver. When facing zone coverage, this combination puts the cornerback in conflict. If he sits on the hitch route, the corner route should be open over the top; if he sinks to the corner, the quarterback takes the easy completion underneath.

With many defenses implementing some form of pattern matching after the snap — a hybrid man/zone coverage in which defenders wait for the receivers to declare their routes before picking them up in man coverage — it’s important for the offense to have complementary pass concepts that appear similar after the snap before breaking differently at the top of the route stem. In Kelly’s offense, smash and levels often work together in this manner.

Scroll back up to the levels image and you’ll notice that it looks strikingly similar to the smash pattern shown above. The one change, of course, is that the receiver who was running a dig route is now running to the corner. For a defense playing pattern-match coverage, the release and break point of the route are the same. The change doesn’t come until after defenders have already been forced to pick-up their respective receivers, giving leverage to the receiver.

When facing pure man coverage, the quarterback is simply looking for the best matchup. More often than not, that means the corner route to the trips side or the alert route on the backside. "Once [the quarterback] realizes it’s man, you’ve got two verticals on a free safety, so he leans him to whoever he’s not going to throw it to," Kelly explained, which as you might remember, mirrors the quarterback’s responsibility on four verticals.

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Tomorrow, we’ll add a third receiver to the mix and look at the many 3-level vertical stretch concepts in Kelly’s passing game.