About Football Defenses

Every football team at every level has a base defense. The base defense dictates where the 11 defensive players are situated on the field. But within those base defenses are several variations designed to prevent offenses from moving the ball down field. And on every play, each defensive player has an assignment. To learn about defense in football, a knowledge of base defenses, their variations and the assignments of defensive players must be understood.

Types

The basic types of defensive football formations are the 3-4 and 4-3. The 4-3 is the most popular. It features four defensive linemen in a three-point stance at the line of scrimmage and three linebackers behind them. The 3-4 boasts three down linemen and four linebackers. In both cases, there are also four defensive backs. Included are two cornerbacks who are responsible for direct coverage of wide receivers, as well as a strong safety, who helps cover the tight end or the most dangerous receiver. The fourth defensive back is a free safety, who helps out anywhere he is needed.

Function

The basic responsibility of any defense is to prevent opposing offenses from scoring. The 4-3 defense is generally believed to be the strongest against the run because it features four defenders up front. It is also beneficial against the pass because the defensive ends are able to rush or even tackle the quarterback. The extra linebacker in the 3-4 defense allows for one or two linebackers to help out in pass coverage against receivers. It also provides another linebacker to plug gaps in the line so running backs are less able to squirt through for long gains.

Expert Insight

Professional football teams rarely utilize anything but 3-4 and 4-3 defenses. High school and small college teams often use a 5-3 defense, in which five defenders are positioned at the line of scrimmage, with three linebackers behind them and only three defensive backs in pass coverage. This is to better stop the running plays, which are far more prevalent at those levels. Most professional offenses pass the ball at least half the time, but many high school offenses run the ball almost exclusively.

Benefits

Among the most advantageous defenses against the passing game is the zone. The zone gives defensive backs responsibility to cover particular areas of the field rather than individual receivers. Though receivers are often able to find "soft spots" in the zone to get open and catch passes, they are less likely to gain yards by running with the ball after the catch because a defender is always in the area. But if a team features very good cornerbacks and a good strong safety, they are best served to play man-to-man defense because they can cover receivers individually, freeing up the free safety to roam and try to intercept passes.

Considerations

Size, strength and speed all enter into consideration when placing players on defense. Defensive ends should be not only big and strong, but quick enough to rush quarterbacks and track down running backs who are carrying the ball around the corners of the line. Defensive tackles should be big and strong and able to engage offensive linemen, prevent holes from opening up along the line and tackle running backs who are rushing the ball inside. Linebackers should be the most athletic of all. They require speed and quickness to make tackles and cover receivers, and strength to fend off blockers. All defensive backs must be fast and quick in pass coverage.

Potential

No defensive set-up can be effective without top talent. Particular defenses can heighten the potential or mask the weaknesses of defensive players. None, however, can transform a defense with bad talent into an effective defense. The best way to maximize the overall performance of a defense is to place each player where he can be of most help. But there is no substitute for practicing together. One mistake from one player can turn an excellent play from his teammates into a touchdown.