Snag, stick, and the importance of triangles (yes, triangles) in the passing game

When Sid Gillman revolutionized and all but invented the modern passing game, he did it through a “conceptual” approach to pass plays based on three “pass concepts”. Because football is governed by its immutable twins of strategy — arithmetic and geometry — these remain the foundation for all effective pass plays:

Simple stuff

  1. Vertical stretches — These place two or three receivers at different levels vertically up the field to “stretch” the defense. Examples include the smash concept and the frontside flood concept (see here for a diagram and here for  a video). Another name for these are high/low or hi/lo reads.
  2. Horizontal stretches — These place two, three, four, or five receivers horizontally across the field or a portion of it to “stretch” defenders from left to right or right to left (or inside to out or outside to in). Examples include all-curl.
  3. Man or “object receiver” reads — These are not necessarily distinct from the above horizontal and vertical stretches, but the focus is on having a route or combination of routes that will defeat man-to-man coverage. Examples include the mesh concept from the Airraid, bunch passes and option-routes.

These three categories essentially made up the full panoply of choices for the passing game for, well, for a really long time. But at some point — most notably with Bill Walsh’s 49ers — a “new” concept began emerging, though it wasn’t actually new at all but was instead a very clever twist on what Gillman had synthesized. Walsh realized that you could combine the horizontal and the vertical stretch to create a kind of “new” stretch, though one made up of both of Gillman’s first two categories. Moreover, Walsh often combined the two zone beaters — the horizontal and vertical stretch — with the third category, the man beating concept, into a single “triangle” read that also was designed to defeat man coverage. If the perfect pass play was the Holy Grail of modern football, then the triangle is its best personification to date and Walsh its Galahad.

But let’s take a step back to understand why the triangle stretch works, along with its negatives. The best vertical or horizontal stretches use more than two receivers, with three or more receivers being used in various “zone flood” routes. If you caught the defense in the right look it was mathematically impossible for them to defend you: If you ran the three-level flood route against Cover 2, they had two guys (a corner and a safety) to defend three receivers; and if you caught a Cover 3/4-under defense with your all-curl concept, it was easy pick’ins:

All this has been detailed before, and if you can identify what coverage you are facing it is still better to run a true three-level vertical stretch or five-receiver horizontal stretch against the right coverage — if you get that right, there’s very little the defense can do. But, of course, it’s not so easy to figure out what coverage the defense is in before the play; indeed, with the advent of combo coverages and pre- and post-snap shifts, it’s often is difficult to even determine what the coverage was even after the play.

Enter the triangle stretch. The insight behind the triangle is that the horizontal and the vertical stretch are combined to create a single straightforward read for the quarterback that provides answers no matter what the defense presents.

All of the major “new” (in relative terms) passing concepts are based on a triangle read. The weakness of the triangle stretch is that it’s typically only possible to only get a two-man horizontal or vertical stretch, whereas with a true “flood” you can place three (or more) receivers across the field on a given plane to truly defeat a defense. This limitation means that a triangle can be throttled by certain coverages that rotate to the triangle side.

But all this is counterbalanced by the triangle’s versatility: the route concept should result in a completion against almost any coverage, and, as will be shown further below, triangle stretches are also usually conducive to having a man-beating concept within them. And if the defense does roll to the triangle side, some kind of backside combination of passes or runs can be used to keep the defense honest. Indeed, the two most popular “triangle” stretches are the “snag” and the “stick” concepts, which are universally used as both ball-control zone beaters and blitz-man beaters. There’s a reason why they have quickly become maybe the most popular pass concepts in football given the simplicity of the throws and the ability to package these concepts with various backside combinations.

The snag is so synonymous with the triangle concept that some teams simply call it “triangle.” The basic concept involves one receiver in the deep third on a corner route (good by itself against man-to-man), one receiver in the flat, often a runningback or inside receiver (which can also be good against man from a bunch-set), and a third receiver on the “snag” route, sometimes also known as a “slant-settle” or a “mini-curl.”


As a general matter, against a Cover Two defense the quarterback will have a high/low read of the quarterback; if he sinks back he can throw it to the inside receiver in the flat; if the cornerback drops he will throw it to the corner route behind the cornerback, as shown in the clip below.

Against a Cover Three defense, the cornerback should take away the corner route by dropping into the deep third, but the snag/mini-curl and the flat should put a horizontal stretch on the flat defender and one of the two should be open.

Putting these two reads together creates the triangle, thus giving options against a variety of coverages. It’s worth mentioning a few points that make the play truly go. First, I prefer this play from a five-step drop. Many coaches teach it from a three-step drop, but I think expanding to a five-step drop allows the corner route to develop so that the high/low read of the corner becomes a better option — the receivers need some time to put that defender in a bind. The important thing is for the corner route to be thrown on “rhythm,” which means the quarterback must throw it once his fifth step hits he must be ready to throw the ball and not require a “gather” or “hitch up” step.

Second, when the quarterback throws the corner route he must “throw the receiver open.” This means that the quarterback must throw the ball to the open space and it is on the receiver to go get the ball. It’s all about attacking space.

Finally, what really makes the play go is the snag or mini-curl or slant-sit route. My preferred way of teaching it is for the receiver to take one vertical step and then to break across the formation to a depth of 5-6 yards over where the corner route originated from. It’s important for him to find the open space. This space should be inside the flat defender but outside the hook-curl defender (typically an inside linebacker), but it could open up in different spots; it’s almost an option route and requires that kind of feel from the receiver. The video clips below show some excellent pro and college examples of effective snags.

Unlike the snag, stick is undoubtedly a three-step drop pass play. Like snag, it is built off of a two-man horizontal stretch and a two-man vertical stretch, even in the same parts of the field; only the routes change. Instead of a corner route, in the deep third, the first read is a simple fade route. The play includes a flat route, which can either be a back or tight-end running a true flat or a slot receiver running a five-yard quick out route. Finally, a slot receiver or tight-end runs the stick route. On the stick, the receiver pushes to six yards and works the soft space between the hook-curl defender and the flat defender, just as on snag. Some teams have the stick player run to six yards and turn inside before pivoting to the outside. Others, primarily in the pros, run it as more of an “out” route though the receiver works back downhill to keep his body between the ball and the defender. Putting these three routes together creates the same triangle read. See the below diagrams from Belichick’s New England Patriots playbook:

Below is a diagram and cut-ups of Y-Stick, the common Airraid version of the play:

But the play is not a “college” or spread offense only play. Indeed, it is probably the single most common pass play in all of the NFL, used by every team as a steady chain-mover and a West Coast Offense staple. And its most capable operator is probably Drew Brees with the Saints. The clip below is excellent evidence, as it shows both Brees’s quick strike ability as well as the freedom the stick receiver has to find the open void in the defense. The defense actually has a good call for this play, as they run a zone blitz and the defensive end drops directly to where the stick should be — no doubt by design. Yet the slot receiver, Lance Moore, does an excellent job sliding just to the inside, which Brees sees and delivers him the football on time in the open space. First down.

Bill Walsh used to say that most of his passing game, and particularly his three-step passing game, was designed simply to take advantage of obvious structural deficiencies in defenses that effectively gave up him those passes by how they aligned. That’s not a luxury modern teams have. Nor do they have the luxury that Sid Gillman had in generally having a good idea of what coverages he’d be facing. Defenses aren’t really different than they were ten, twenty, or even thirty years ago, but they are certainly more multiple and better at disguising their intentions.

To combat these kinds of tactics offenses need answers. And in a game with few easy ones, triangle pass concepts provide a relatively steady, dependable way to continuously move the football. Triangle concepts may or may not be the Holy Grail of passing offense, but they do offer one thing: the opportunity for speed in space. And that’s all that can be hoped for.

Additional reading and viewing:

Colt McCoy’s Texas two-man passing game.

Hanover College’s Black Cat Attack Offense (showing “snag” or “spot” from quads)

Noel Mazzone Snag from Brophy.

Stick and snag against fire zones via Brophy.

BYU Passing Game (excellent).