Determining the pass coverage by “reading the square”

I didn’t invent this, but thought I’d pass it along. Much of it was originated by Lindy Infante, but it is common among most good passing coaches now.

...find the safeties

...find the safeties.

Post-snap reads (“Reading the Square”):

The most important area for determining secondary coverages is the middle of the field about 15 to 25 yards deep and about 2 yards inside of each hash. We call this area the “square”.

We normally read the “square” in our drop back passing game. Reading the “square” becomes necessary when it is impossible to determine what the coverage they are in before the snap or to make sure of secondary coverage after the snap.

In reading the “square” the QB simply looks down the middle of the field. He should not focus on either Safety but see them both in his peripheral vision.

  1. If neither Safety shows up in the “square”, and both are deep, it will indicate a form of Cover 2. A quick check of Corner alignment and play will indicate whether it is a 2/Man or 2/Zone. If neither Safety shows up in the “square” and both are shallow, it will indicate a Cover 0 (blitz look).
  2. If the Strong Safety shows up in the “square”, this will indicate a Cover 3 rolled weak or possibly a Cover 1.
  3. If the Weak Safety shows up in the “square”, this will indicate a strong side coverage. It could be a Cover 3 or a Cover 1. If the coverage is Cover 3, it could be a Cover 3/Sky (Safety), or a Cover 3/Cloud (Corner), depending on who has the short zone.

NOTE: When either of the Safeties shows up in the “square”, the best percentage area to throw the ball in is the side that he came from! If NEITHER of the Safeties show up in the “square” – throwing the ball into the “square” is a high percentage throw.

  • FanofGame101

    I know chris said the majority of the time a sack is the fault of the quarterback not getting the ball out fast enough. If you do decide to read the square what is the time frame all this should be done in?

    “We normally read the “square” in our drop back passing game.”

    Also do you not read the square in the shotgun?

  • Please write a book.

  • I just learned about you guys and your site, and I love it. I wish more football fans would read stuff like this.

  • Jno

    You’re right BELLANCA!
    please write a book

    So , let’s start a “petition” ?

  • FanofGame101

    Chris, also how do you decide when to stay with a 1,2,3 read vs. the read of the safties?

  • An excellent picture to go along with the post. I saw every game Brees played at Purdue from the press box and after his Junior year I was convinced he was the most complete passer the Big Ten had seen in quite a while (and since). I think in 15 years of watching the Big Ten there were two players I saw who convinced me beyond a shadow of a doubt that they were ready for NFL offenses and it was Brees and Joe Thomas. Brees beat a good Ohio State team by simply reading the safeties and throwing out routes to the back side of the coverages. I guess you can sell seats in the NFL on arm strength but it sure seems like brains and accuracy win games.

  • Mr.Murder

    The nearest route with a vertical stem, who squeezes it? If is squeezed from the strong safety read outside, if it squeezed from mike read inside.

    Square read and mofo/presnap seem to compliment so well, just read who fills the square and throw to that side a route outside of the square?

  • Willard Mountjoy,

    I learned pass offense personally from Sid Gillman AND Lindy
    Infante. Lindy taught to progress to the side in which the “Best
    Located Safety” entered the “SQUARE” (for diagrams = CONTACT ME by phone

    Sid Gillman advanced a critical concept that all quarterbacks abide by
    today: the “best-located-safety” principle. By that, he meant a passer
    should throw the ball to the receiver who is located the farthest from
    either safety on the field. The principle worked for his Chargers
    quarterbacks, it worked for me throughout my coaching career, and it’s
    still a cardinal rule for today’s NFL passers.

    The starting
    point for reading MOST of patterns, especially the Horizontal Stretch
    patterns, begins with the BEST LOCATED SAFETY principle. In our
    terminology “B.L.S.” is the Safetyman furthest removed from the wide
    receiver. He has a greater distance to to move to get involved with
    defending a wide receiver than the other Safety. We see defenses that
    might look like they are lined up in a 3 Deep. We normally face a 7 Man
    front with 4 Deep. The QB comes up to the line and takes a PRE-SNAP
    LOOK, we call it “PSL”, and he looks for both Safeties. If one of the
    two Safetymen is furthest removed from one of our wide receivers, then
    that Safety becomes the BEST LOCATED SAFETY. We call that side the
    “BLS” side of the defense therefore we are going to attack with the
    pattern called. He has less chance of doubling up on our wide receiver
    because he is not as close as the other Safetyman. Not all patterns are
    “BLS” read patterns. Some patterns require another read due to the
    specific design of the pattern. However, all MIRRORED patterns are
    “BLS” reads.

    Coach Bill Mountjoy

    Richmond Va 804-716-7038

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