American Football 101, Part 2: The Defensive Side | Thebigtip

In part 1 of our series we discussed the offensive side of football. We explored their job, what each position does and also mentioned some of the terminology used.

Now we will look at the defensive side of football.

We will see the most popular defensive structures most teams will line up in as their base (the standard defense used and has on variations) defense.

We will also look at some of the terminology that is associated with defense.

The Job of the defense

The job of the defense is simple - to stop the offense from scoring.  This can be accomplished in several ways.

The most common way is to force the offense to punt the ball. To do this they must keep the offense from gaining first downs. So the defense wants to stop the offense from gaining 10 yards.

The defense has to stop the offense from gaining a total of 10 yards on 1st down, 2nd down and 3rd down and rarely on 4th down when the offence is behind points wise or the offense is gambling for momentum.

(Sometimes the offense will go for a 1st down on their 4th down.  To achieve this, the offence will try to acquire the yardage needed for a new first down on fourth down instead of punting the ball.  If the offense fails to gain the new first down they turn the ball over on downs to the other team. So the defense will be called upon to stop them from gaining the required 10 or more yards).

Note: We will discuss some of the ways the offensive can lose yards by penalties or gain yards on penalties in our next segment of this series. In which we will discuss the field and the officials in part three of this series.

The defense also can stop the offense from scoring by getting or creating turnovers (when the offense turns the ball over to the defense). This can be done one of two ways.

The first way the defense can stop the offensive using turnover is by recovering or causing fumbles. A fumble is when an offensive player losses possession (they no longer have it in their hands) of the ball.

This can be caused by striping the ball (defensive players using their hands to rip the ball out of the offensive player’s hands). The other ways to cause a fumble is by hitting an offensive player hard enough to dislodge the ball from his possession.

The second way to make the offensive turn the ball over is by intercepting the ball. This is when a defensive place intercepts (catching a pass meant for an offensive player) the ball.  The same rules that apply for an offensive player to catch the ball are the same for a defensive player.

For a catch to be made a player must have the required number of feet in bounds (one for high school and college and two feet for pro football) and possession of the ball (when the play has the ball securely in their hand and next to their body).

Whereas only Running Backs, Fullbacks, Tight Ends, Wide Receivers and sometimes Quarterbacks can catch the ball on offense. Every player on the defensive side of the ball can catch a pass (or the ball) no matter where they are playing or where they line up at.

Common defensive formations

In the first part of our series we discussed the positions first then the formations when we discussed the offense. Defense is different in fact that they are not constrained by having to line up a certain spot or way.

The defense can line up anywhere on their side of the ball and they do not have to have a certain number of players on the line of scrimmage (remember the offense must have seven players on the line of scrimmage).

Secondly the defense can move any direction before the snap of the ball (the offensive can only move horizontally or parallel to the line of scrimmage and must be set or stopped at least a second or two before the snap of the ball).

The defense can move forward, backwards, or from side to side and does not have to be set at all before the snap of the ball. The defense can also switch positions before the snap of the ball (this will be discussed later).

Two of the most used defensive formations are the 3-4 and the 4-3. There are several other defenses used but these are the two most common.

3-4 Defense

 

 

 

 

 

 

 

 

 

The 3-4 defense gets in name because it from the fact it has three down linemen (a defensive line men with a hand down on the ground like an offensive lineman) and four linebackers.  Just like most defenses there are also two safeties and two cornerbacks.

The idea behind this defense is that the offense does not know which four players will rush the line of scrimmage (basically which defenders are defending against running plays on the line of scrimmage or rushing the quarterback).

The defensive will move players all around to try to confuse the offensive line as to who they should be blocking on each play. The 3-4 defense is predicated on speed by the linebackers. So the defense will give up size on the defensive line to have more speed at linebacker.

The defensive line that are used in the 3-4 defense typically tend to be larger and stronger to try to force more focus of the offensive linemen on them and not the linebackers. To do this the defensive linemen line up directly in front of the offensive linemen. 

They have two gap responsibilities which means they read the offensive linemen to see which way the play is going and to hold up the offensive linemen from the linebackers. Defensive line men in this formation are not expected to make a lot of tackles.

Linebackers are used to cover gaps or shoot gaps in the offensive line. The linebackers are expected to make most of the tackles in this defensive formation.  Since the three down linemen are taking up the offensive line attention the linebackers should be free to clean up plays or make tackles.

Note: The alignment or where a defensive player lines ups at and gaps will be discussed later.

4-3 Defense

 

 

 

 

 

 

 

 

 

If the 3-4 defense gets its name from having 3 down linemen and 4 linebackers to make up its formation it should be easy to figure out how the 4-3 defense its name. So the 4-3 defense must get its name from having 4 defensive linemen and 3 linebackers.

The idea behind this defense is for the defensive linemen to contain the running game. To do this the down lineman must control their gap responsibilities. The down line men are also responsible for rushing (try to tackle) the quarterback.

The linebackers have gap responsibilities on running plays but their first job is to make sure the play is not a passing play.  The first move of the linebackers is backwards to cover the short passing game.

Defensive players switching positions

This is basically when defensive players switch responsibilities. A defensive lineman will cover the linebacker’s job and vice versus.

This can be done pre snap with the linebacker becoming a down lineman before the ball is snapped and the lineman standing up taking the linebackers position. The players can switch after the snap with linebacker rushing forward to do the lineman’s job and the lineman rushing backwards to cover the linebackers job.

The defensive secondary can do this as well. This happens when a cornerback rushes the line of scrimmage (called a corner blitz) and the strong safety or free safety covers a wide receiver.

The defense does this to try to confuse the offense as to what they are doing to try to stop the offense. The defense will move around (often moving from side to side or back and forth) and fake what they are doing in effort to disguise what they are really doing.

Note: The all of other jobs or responsibilities of each position on defense will be discussed after the Nickel and Dime defense.

Two other popular defenses the Nickel and the Dime.

Nickel defense

The nickel defense gets its name from the fact that there are five defensive backs (corner backs and safeties) on the field.  This defense is used when the offense adds a third or fourth receiver to its formation. The defense normally adds a third cornerback but can add a safety as well.

This can be done by taking a defensive lineman a linebacker off the field. Who is taken off the field is determined by the type of defense that is played and the abilities of the players already on the field.

Most often in a 3-4 defense a linebacker usually is taken off the field to make up the nickel. To make up a nickel in the 4-3 defense a defensive lineman is usually is taken off the field. This does not mean that the player will be a lineman in the 4-3 or a linebacker in the 3-4.

Dime defense

The dime defense gets its name when the defense adds a sixth defensive back or second nickel back. Since two nickels makes a dime hence the name.  This defense is used when the offense goes to four or five receivers to its formation.

To make up the dime defense normally the takes off two linebackers. In the 3-4 defense both of the outside linebackers come off the field.  In the 4-3 defense a defensive lineman and a linebacker can come off the field or both outside linebackers can come off the field.

Once again the player taken off the field depends on the abilities of the players on the field most commonly done is a linebacker is taken off the field. The player taken off the field also depends on the defensive philosophy used by the defensive coordinator and the head coach (coaches will be discussed later).

(Click here to see other offensive or defensive formations)

Defensive positions and their jobs of the field (can change according to the responsibilities of the defense that is called or the abilities of the player on the field)

Defensive Tackles: Used in the 4-3 defense or in the 3-4 when the tackle is not lined up in front of the center. They line up in the middle of the defensive line. The defensive tackle’s job is to take on offensive linemen to help the free up the linebackers.

The Tackles also make tackles (take a ball carrier to the ground) in the running game their first responsibility and rush the passer (rushing the passer means try to sack the quarterback or tackle the quarterback).

Nose Guard: Used in the 3-4 defense when a Tackle is lined up straight up in front the center. The Nose Guard has the same responsibilities as a defense tackles.

Defensive Ends: Defensive ends line up at the end of the defensive line. They have run responsibilities first and then rush the passer if it is a pass play. Defensive ends are sometimes be used in pass coverage as well. The defensive ends also have containment responsibilities as well.  

Containment is when a play goes out wide or toward the side line and the defensive player must turn the play back to the center of the field.  The reason a defense player wants to contain a play to the outside is for two reasons.

First there are only a few players to the outside to make a tackle. Second, if the defense can turn the back to the center of the field there is more help to make the tackle.

Linebackers: Linebackers like defensive linemen run responsibilities first. Then either rush the passer or drop into pass coverage. Depending on the defensive scheme called determines if a linebacker covers the pass or rushes the quarterback.

There are two types of linebackers in football. There are outside linebackers and inside or middle linebackers.

Outside linebackers have containment responsibilities and where they line up depends on the strong side of the offense. There are strong side linebackers who line up on the strong side of the offense and weak side linebackers who line up on the week side of the offense.

Middle linebackers line up in the middle of the field or in the middle of the outside linebackers. Both sets of linebackers help against the run, drop into pass coverage, and rush the quarterback.

Corner Backs: The first responsibility is to cover receivers on passing plays. If the offense runs the ball the corner backs do not help on a run until the ball carrier cross the line of scrimmage (this is because the ball cannot be passed forward anymore). They are also used to rush the quarterback as well.

Note: How to cover a receiver. A cornerback, strong safety, and free safety do most of the pass defense (other pass defense terminology will be discussed later). A defender can only touch a receiver for the first five yards after the ball is snapped. The defender cannot touch defender again until the ball the exact moment the ball arrives to the receiver. The defender may catch the ball or bat it away as long as he does not interfere (illegally impairing the receiver chance to catch the ball) with receiver.

Strong Safety: The strong safety lines up on the strong side of the field. Strong safeties are used to help stop the run first and for most.  The strong safety is used in pass defense and can be used to rush the quarterback as well.

Free Safety:  Free safeties are mainly used in pass defense. The free safety earned its name by playing the deepest defensive position and is free to roam the field. The free safety is mainly used in pass defense. Although they can help with run defense or rush the quarterback.

Note: Safeties are the last line of defense. They are not supposed to let any offensive player deeper than they are. Some times on pass defense the safeties split the field in half with each safety covering one side of the field. Strong safeties are known more as hitters and free safeties known to be better covering receivers.

Ways the defense can score points

There are three ways the defense can score points. The first way is picking up a fumble and running it back for a touchdown. The second way is returning an interception for a touchdown. The last way is to tackle a defensive player in their own end zone (the end zone behind the offense). When the defense does this it is called a safety and is worth 2 points.

Defensive Terminology

1. Blitz- This term is used when a linebacker or a defensive back that normally stays back from the line of scrimmage on a pass play rushes the quarterback or the ball carrier. There are passing blitzes and run blitzes.

2. The Box- An imaginary box on the defensive side of the ball that includes the defensive linemen and linebackers (seven defensive players are normally line up in the box) that are used to stop the run.

3. Eight men in the box - A term used when the defense brings an eighth defender in to the box. This is used to stop the running game.

4. Pick- Another term for an interception.

5. Pick 6- An interception that is run back for a touchdown.

6. Take it to the house- A fumble or interception run back for a touchdown.

7. Stunt- A term used when defensive linemen try to confuse the offensive line by switch position. Most stunts are used on passing downs (downs in which the offense will more than likely pass the ball).

8. Bend but not break- This refers to a defense that gives up a lot of yards to an offense but does not surrender any or few points.

9. Penetration- When a defensive player is able to get in to the offensive back field.

10. Zone Blitz- When a defensive lineman switches places with a linebacker or a defensive back. The defensive lineman drops back in pass coverage while the linebacker or defensive back rushes the quarterback.

11. Tampa Two- A defensive strategy made famous by the Tampa Bay Buccaneers in the late 1990’s by head coach Tony Dungy and Monte Kiffin. This defensive scheme puts a high value on speed at all the defensive positions.

12. Prevent defense- The prevent defense is used by the defense when the offensive is behind in points late in a ball game. The defense adds seven or more defensive backs. Since the offense is behind and trying to score quickly they will use the pass exclusively. Which is why the defense will put more defensive backs in to the game and tries to keep all of the offensive players in from of them.

13. Man to Man defense- Used by the defense in passes coverage. Man to man is when each defender in the pass defense has a man that is their job to cover on passing plays. They are responsible for keeping up with that receiver no matter where he goes on the field.

14. Bump and run- A defensive scheme where the safeties and the cornerbacks will get right on top of the line of scrimmage. At the snap of the ball the defensive back (safety or cornerback) will try to bump or jam or hold up the receiver with his hands. This is used to try to mess up the passing timing between the quarterback and receivers on passing routes.

15. Zone defense- A defensive pass coverage. Instead of playing pass defense on one player the defensive players in pass coverage play defense on a certain part of the field or area of the field. When a receiver comes into the defender’s area he covers the receiver. When the receiver leaves the defender’s area he let the defender in the next area pick up the pass coverage on that receiver.

16. Technique- This tells you where the defensive lineman lined up.

17. Gap- This tells you where the defensive lineman’s run responsibility is at.

(Click here to read more about technique and gaps)

18. Numbers- Defensive players can wear any numbers in college and high school. The NFL or pro football has rules as to what numbers can be worn by players.

Defensive linemen numbers: 60-79 and 90-99

Linebackers numbers: 50-59 and 90-99

Cornerbacks and safeties numbers: 20-49

This concludes our look at the defensive side of football. Now you have the two biggest parts of learning football. The offensive and defensive sides of football are the two most involved parts of football.

Next we will discuss the job of the officials in football. We will look at who each of the officials are and what their job is. We will also look at some of the most common penalties called in football.

This will lead us up to our final installments when we will discuss the kicking game and putting it all together. We will look at kickoffs, kickoff returns, punts, punt returns and field goals.

Also after we get done looking at the kicking game we will discuss some of the jobs of coaches.

Part Three will be on football officiating and will be out tomorrow.