Today, class, we're going to discuss the basics of playing defense in football. If I do this right, you'll be able to watch a game on TV and have a faint idea of what the hell they're doing.

Positions

There are three types of position in defense: lineman, linebacker, and back. They are pretty self-explanatory. Here's a diagram of a standard 4-3 defense, which we'll explain in more detail in a sec:

               -------------------- (line of scrimmage)
                  DE  DT  DT  DE    (linemen)

                OL      MLB     OL   (linebackers)

            CB                        CB
                   SS            FS   (backs)

Linemen are either defensive ends or defensive tackles, and stop the run or rush the QB; linebackers are either outside, inside or middle, and go where the ball goes (more or less); backs are either cornerbacks or safeties, and defend the pass. The four basic defensive alignments are named according to the number of players in each position.

Formations

  • The 4-3 defense, diagrammed above, features four linemen and three linebackers. It is the bread and butter of a defense and almost every football team spends half the game in this formation. The emphasis is on stopping the run and the short pass
  • The 3-4 defense, which features three linemen and four linebackers. With the right personnel, it can be more effective than the 4-3; you need smart, fast linebackers and REALLY powerful linemen who can pressure the quarterback without help from the linebackers.
  • The nickel takes out one linebacker from a 4-3 and adds an extra defensive back, giving 5 total backs. This is good when you suspect a pass play, since the backs are better at stopping passes than the linebackers.
  • The dime goes a step further and replaces another linebacker with a back, giving 6 total backs. This is used when the defense is willing to mortgage the farm that the next play will be a pass. It is very strong against a long pass but practically concedes the short pass outright.

Actions

There are several standard moves and bits of jargon used on defense. They describe a player's role after the play has started, and they are the same in all formations. Strategy arises when directing players in a given formation.

  • Types of pass coverage
    • Zone: The field is divided into a number of zones equal to the number of linebackers and backs. Each zone is assigned to a linebacker or back. He waits for a receiver to enter his zone and covers him when he does, releasing him again when he leaves it.
    • Man-to-man: The linebacker or back is assigned to a specific receiver and attempts to cover him for the length of the play.
    • Bump and run: The linebacker or back tries to knock the receiver off his route by pushing or blocking within 5 yards of the line of scrimmage. Such contact outside this area is a foul.
  • Blitz: A linebacker or back rushes the offense in an attempt to tackle the ball carrier behind the line of scrimmage. This is a gamble: however many guys you blitz will not be available to defend the pass once it's thrown.
  • Interception: A defensive player has as much right to play the ball as an offensive player does. If a defender catches a pass, his team gains possession and the defense becomes the offense immediately (and vice versa).
To expand on Deadbolt's mention of pass coverage, I'd like to discuss the coverages more in-depth

  • Zone: Typical assignments:
    • Cover Three: the most usual (that I've seen). The field is divided into thirds, for two cornerbacks and one free safety. The linebackers cover the flats.
    • Cover Two: slightly less well-known. The field is divided in half, with two safeteys (free and strong) and the two cornerbacks covering the flats.
    • Cover Four: unusual, also called the Umbrella coverage. You guessed it, field is divided into fourths, the corners on the outside and the safeteys on the inside. Can be turned into a Cover Two by sending either of the two back up to the flats.
  • Man-to-man: not much variations on this. Our defensive coach always said "You stay with him until that whistle blows. He goes to the bathroom, you wipe for him" and that's how close you have to stay with him, anticipating his moves.
  • Bump and run: is actually a kind of man-to-man, bumping him at the line then following him. Usually a second or two is all that it takes to end a receiver's chance of getting the ball, but if the bump doesn't buy you enough time, the coverage will discourage a pass.
and here are the zones:

          - - - - - - - - - - - -     (line of scrimmage)

              |               |
      C       |       S       |        C
              |               |

                 Cover Three


          - - - - - - - - - - - -     (line of scrimmage)

      C               |               C
                      |
              S              $

             Cover Two


          - - - - - - - - - - - -     (line of scrimmage)

          |              |             |
   C           S             $            C

              Cover Four

Log in or register to write something here or to contact authors.