Football 301: Defense - Chaos, Intimidation, & Improvisation

"A linebacker is like an animal. He's like a lion or a tiger and he goes after prey. He wants to eat him, he wants to kick the sh-t out of him. That's a linebacker,"
--Chuck Bednarik

The three elements in American football related to stopping an offensive from succeeding are chaos, intimidation and the ability to react quickly and improvise.

As noted in the section on offense, the keys to a good offense are often the set, choreographed plays which the offense spends months working on. Often offensive players are known to be extremely disciplined athletes; as doing exactly what they are supposed to do on every given play is crucial to their team's success. One player screwing up by missing a block, or not being at the right place on the field at the right time, can mean the difference between winning and losing. Offensive players learn huge playbooks -- complicated tomes of hundreds of plays.

Defense is different. The goal of the defense is to screw up the offense as much as possible by causing as much chaos on the field as possible and to intimidate the opposing offense in an effort to distract them from carrying out their plays correctly. If neither of these efforts work, defenses must have incredible athletic skills to react to the play at hand and improvise. As a result often the very best athletes on the field, and certainly the meanest, are defensive players.

Intimidation

Defensive players, like their offensive counterparts, generally have specific jobs, although usually far less specialized than the offensive squad. Most teams use seven of their eleven players to defend close to the line of scrimmage, as either defensive linemen (who crouch down opposite the offensive linemen), or as "linebackers" who usually line up just behind the defensive linemen. These players share two jobs -- perhaps the most important on the field -- tackling the ball carrier if the offense tries a running play, and getting in the face of the quarterback so that he/she has a hard time throwing a pass. When the quarterback is tackled before he/she can throw a pass it's called a "sack". Defensive players love sacks.

The four remaining defensive players are called "Defensive Backs". Their job is to intercept or knock down any passes, or prevent the wide receivers from getting to the ball. These positions demand incredible athletic ability as they must have the speed to match the wide receivers and the agility to react quickly to the receiver's "routes" (the choreographed paths which the Wide Receivers run). Sometimes the linebackers will drop back to help cover receivers as well.

Players can be substituted for whenever a play ends. So extra defensive backs may replace linebackers when the coach thinks the opposing team will try a passing play, and extra linebackers mayl replace defensive backs when the coach thinks the opposing team may try a running play.

Some Basic Concepts

There are several basic concepts that define defenses in football. The first is regarding how the defensive backs and linebackers cover receivers. Depending on the situation the "coverage" will be either "man-to-man" or "zone". "Man-to-man" means that defensive backs try to stay with one receiver throughout the play. They're responsible for that receiver--keeping on him/her as the receiver twists and turns and tries to get open to catch a pass. "Zone" coverage means that defensive players are responsible for an area on the field. They react to any receiver who comes into their zone, but let him/her go, once they've run out of their zone. This is a useful technique particularly when the defense thinks that the offensive is about to throw the ball far downfield. A defensive back in a zone can see the whole field pretty well (at least what's in front of him/her) and can move to the ball, once it's thrown. Players in zone coverage often try to "read" a quarterback -- looking at his eyes to see if they can deturmine where the ball might be thrown. A defender in man-to-man coverage can't usually look at what the quarterback's doing, as the focus must be on the receiver who's trying to squirm away. On the other hand a good man-to-man coverage makes sure that the receivers have a hard time catching the pass.

Most teams mix up man and zone coverage. Some defenders cover receivers man-to-man, while others watch the quarterback and react to where he/she is throwing.

Meanwhile, of course, the quarterback is watching the defense carefully and makes decisions on where to throw the ball on what he/she sees. Certain plays work well against zone defense; certain plays works better against "man" defense. In fact the offense will usually do a variety of tricky things to see what coverage the defense is using. Football is often about figuring out what the other team is doing. A team with poor athletic skills but with smart players and coaches can often beat a team with better athletic skills.

The Blitz

A blitz is a defensive play where defenses send players directly at the quarterback, in an attempt to get a sack or to fluster the quarterback into throwing a bad pass. This is done by either sending in more players than the offense can block, or by sending players from odd angles and directions, hoping to catch the offense off guard.

Quarterback looking for a receiver -- as opposing players blitz. (Texas high school game, ca. 1915)

A blitz can be incredibly effective although it can be risky. If the defense sends in extra players they risk leaving a receiver wide open. Good offenses will burn a blitzing defense but good.