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How American Football Works


Football Defense and Special Teams

When a team does not have possession of the ball, it is on defense and uses various methods to prevent the other team's offense from scoring. These players must tackle the offensive player who has the ball to stop the offense from advancing. Defense will also try to take the ball away from the offense.

Here are the basic defensive positions:

  • Defensive linemen - The linemen put pressure on the quarterback by trying to tackle him before he releases the ball. They also try to stop running backs. There are typically three or four defensive linemen. Individual positions include Ends (LE/RE), Nose tackle (NT) and Tackle (LDT/RDT). The ends line up on the outside of the line and try to rush around the offensive tackles. The nose tackle lines up over the football. The tackle lines up across from a guard and tries to knife through the offensive line.

  • Linebackers - When there are four linemen, there is a middle linebacker (MLB) and two outside linebackers (OLB). When there are three linemen, there are two inside linebackers (ILB) and two outside linebackers. Their job is to back up the linemen, as well as contain runners and cover receivers on some plays.

    Philadelphia Eagles at play
    Photo courtesy The Philadelphia Eagles
    #51 in this photo is a linebacker

  • Cornerbacks (CB) - The cornerbacks prevent the wide receivers from catching the ball by breaking up passes from the quarterback.

  • Safeties - The safeties play deep behind the rest of the defense to prevent a long pass or run. A strong safety (SS) lines up on the side of the field where there are more offensive players. The free safety (FS) plays a deep, middle position.

Special Teams

football placekicker
Photo courtesy The Philadelphia Eagles
Placekicker

If a team has to kick the ball, it uses its special-teams unit. This unit includes the team's kickers, the offensive line, and players who run down the field to tackle a returner (see below).

  • Placekicker - The placekicker kicks the ball through the goalposts to score points and kicks the ball to the other team to start the game and after each scoring possession.
  • Punter - The punter free-kicks the ball if his team cannot advance the ball down the field.
  • Returner - During a kickoff or punt, the returner tries to catch the ball and return it as far as he can. A player can score a touchdown on a return.

In the next section, you will learn more about how teams move the ball and how the down-and-distance system works.