Welcome to Football 101 presented by The Painted Lines! In this ongoing offseason series, I will be breaking down football concepts to help you better understand what you are watching on Sundays. Each article will take a deep dive into a specific component of the game. We will also be updating a cheat sheet throughout the series that you can bookmark or print out for quick reference on game days. You can also join our public discord to interact with our writers and podcasters and talk X’s and O’s.

If you have missed any of the previous articles of this series you can check them out below:

Without further adieu, let’s dive in!  Today we are going to take a look at offensive and defensive personnel groupings

Offensive Personnel Groupings

A personnel grouping is the group of players that a team puts on the field in a given situation. Offensively the groupings are assigned numbers and defensively they are assigned names.

An offensive grouping is given a two-digit number to represent it. The first number represents the number of running backs on the field and the second number represents the number of tight ends on the field. The number of receivers on the field is five (the total number of eligible receivers on every play) minus the two listed numbers. For example, 21 personnel signifies 2 running backs, 1 tight end, and 2 receivers on the field.

Offensive Personnel Groupings

Inside of each personnel group a multitude of different formations can be called. For example, in 11 personnel you can put all 3 WRs on the same side of the field in a trips formation or you could put 2 on one side and 1 on the other side. You can put the QB under center, in the pistol, or in the shotgun. You can split the RB out as a WR or you can put him in the backfield. You can utilize numerous different looks out of the same personnel group.

In the NFL the most frequently used grouping is 11 personnel. According to Sharp Football Stats, 11 personnel was used on 60% of offensive plays league-wide in 2020. Every team in the NFL used 11 personnel as their primary offensive personnel grouping. The next most commonly used groupings are 12 personnel (20%), and 21 personnel (7%). What is interesting to note is that when you look at offensive success rates across those 3 groupings you find that both 12 and 21 personnel have a higher success rate* (51%) than 11 personnel (48%).

*Success rate is a metric that measures efficiency inside the context of down and distance.  A play is considered successful if it gains 50% of the yards to go on 1st down, 70% of the yards to go on 2nd down, or 100% of the yards to gain on 3rd or 4th down.

Defensive Personnel Groupings

The defense will typically deploy its personnel to match the offense. Generally speaking, if an offense puts 3 WRs on the field then the defense will put 3 CBs (or 2 CBs and an extra safety) on the field to match the offense. Because of this, the offense can have a major impact on what players the defense put on the field. Does the opposing defense have a major injury at linebacker or poor linebacker play overall? If so, the offense might want to run a lot of plays with only 2 receivers on the field (12 or 21 personnel) to force the defense to deploy a lot of linebackers in the defense. Conversely, when playing a defense that has great linebacker play the offense may want to put a lot of receivers on the field to force the defense to counter by taking linebackers off the field and replacing them with cornerbacks.

Each team has a “base” defense. This is the defense that they prefer to run and build their defensive philosophy around. There are 2 options for a base defense: 4-3 and 3-4. The first number in these formation names refers to the number of defensive linemen on the field while the second number refers to the number of linebackers. In a 4-3 formation the defense will have 4 linemen, 3 linebackers, 2 cornerbacks, and 2 safeties. In a 3-4 the number of cornerbacks and safeties are the same but the number of linemen and linebackers are flipped.

From that base defense, the team also has several other formations that they will run to adjust to the offense.

  • Nickel – Nickel defense removes a linebacker from the field and replaces him with a defensive back. It is called nickel because a nickel is worth 5 cents and a nickel formation puts 5 defensive backs on the field. For a 4-3 team a nickel defense is typically 4-2-5 (4 linemen, 2 linebackers, 5 defensive backs) while a 3-4 team will use a 3-3-5 setup.

  • Dime – Dime defense removes an additional linebacker from the field in favor of another defensive back. It is called dime, not because there are 10 defensive backs on the field, but rather because it is the next step up from nickel and flows off the tongue better than “nickel and a penny” does. A 4-3 team will typically use a 4-1-6 grouping while a 3-4 team will use a 3-2-6 grouping.

  • Quarters – Quarters defense is only used when the defense is certain that the offense is passing the ball. It puts 7 defensive backs on the field and because of this is extremely vulnerable to the run. Both 4-3 teams and 3-4 teams typically utilize a 3-1-7 grouping for this defense.

  • Goalline – Goalline defense is a heavy defensive formation usually utilized in short-yardage situations or at the goal line. It will put 5-6 defensive linemen on the field and crowd the box with additional linebackers.

Defensive Formations

That concludes our primer on personnel groupings. Don’t forget to go back and check out our article on coverage shells if you missed that and click on over to the cheat sheet if you want to review the strengths and weaknesses of different alignments. The links for both are at the top of the page.  Keep it tuned to the Painted Lines for our Football 101 series and let us know if there is something, in particular, you would like us to cover.  Next week we will make the jump to the offensive side of the ball and dive into offensive line play by breaking down the differences between man blocking, zone blocking, and combo blocking.