The defensive team in American football aims to prevent the other team from scoring. Defensive positions can be grouped into three categories: defensive linemen, linebackers, and defensive backs. Defensive linemen prevent the offense from running the ball and speed up the passer. Linebackers focus on run breaks and pass coverage, while defensive backs defend against the pass. Players may move around the formation, and aggressive stances are necessary.
The defensive team in American football is the team that does not have possession of the ball and is trying to prevent the other team’s offense from scoring. There can be 11 players in various positions on the field for defense on a play, just as they can be for offense. Defensive positions in football can be grouped into three general categories: linebacker, linebacker, and defensive back. Defensive linemen generally line up closest to the ball, along the line of scrimmage, as exemplified by the white-shirt players pictured below. Linebackers are usually a little behind the defensive line or a little to the side, and defensive backs are usually furthest back or furthest out to the side.
There are two types of positions on the defensive line: tackles, which are positioned closest to the ball, and ends, which line up outside the tackles. These are usually the bigger defensive players, with the tackles typically heavier than the ends. Most often, these players line up in a crouched position with one hand on the ground – as seen in the following photo – in what is called a three-point position, or with both hands on the ground in a four-point position.
Some defensive formations use two ends and two tackles, but others use two ends and a tackle, in which case the tackle is usually called a nose tackle or nose guard. When the defensive formation uses two tackles, one might be referred to as a nose tackle and the other under tackle. In some situations, or more frequently in leagues for younger players, a defense might use five or more defensive linemen. In such cases, along with two ends, a defensive line might include a nose guard and two defensive tackles, two guards and two tackles, or players in positions that go by other names like these.
One of the main jobs of defensive tackles and defensive ends is to prevent the offense from successfully running the ball, either by holding ground against offensive blockers or by avoiding blockers and tackling the offensive player who is carrying the ball, as seen in the photo above. When the offense tries to pass, the defensive linemen’s main job is to speed up the passer. That is, they try to tackle the quarterback before he or she can throw the ball, which is called sacking the quarterback, or at least get close enough to disrupt the quarterback’s throwing motion. In the following photo, the defenders – the ones in the yellow jerseys – are running up to the quarterback, who has the ball.
The second tier of defense is formed by the linebackers. Most of the time, the two linebackers who line up furthest to the side are called the outside linebackers. They might line up directly behind the defensive ends or behind and a little to either side of the ends, or sometimes they’re in the line and out of the defensive ends. Behind the linemen and toward center field, a defense might have one linebacker, called a middle linebacker, or two linebackers, who would be called inside linebackers. Most linebackers take their stand or slightly crouch position, as seen in the photo below, but outside linebackers occasionally line up in three-point positions when they’re on the line and off defensive ends.
Linebacker responsibilities depend on defensive strategy and whether the offense is trying to run or pass the ball. Inside or intermediate linebackers typically focus more on the run break. If the offense tries to pass, however, they may have to cover for a potential receiver, defend a particular part of the field, or assault the passer. Outside linebackers typically have similar responsibilities, but in some defenses—primarily those called 3-4 defenses, which utilize three linebackers and four linebackers—outside linebackers are much more likely to rush the passer. Middle or inside linebackers typically are sturdier than outside linebackers, who are usually taller and faster.
Outside linebackers are sometimes utilized on a particular side of the offense, the strong side or weak side, which are determined by the alignment of the offensive players. In these cases, they are usually called the strong side linebacker and weak side linebacker, respectively. They could also be called linebackers “Sam” and “Will” for short, with a lone middle linebacker being called “Mike” or the two inside linebackers being “Mike” and “Ted”. An outside linebacker throwing a pass in a 3-4 defense might be called a “Jack” linebacker using these naming conventions.
The smallest and fastest players in defense typically are the full backs, who are collectively referred to as the secondary. The cornerbacks are lined further outfield and may be close to the line of scrimmage or up to 10-15 yards (about 9.1-13.7 m) behind it. The safeties usually line up further back and toward center field.
Most defenses use two cornerbacks and two safety. When each security has slightly different responsibilities, one might be called a strong security and the other a loose security. A strong safety is usually larger and a loose safety is usually faster. When the offense is most likely to pass the ball, the defense might replace one or two linebackers or defensive linemen with additional defensive backs. A fifth fielding defender would usually be called the nickel back, and a sixth would be called the dime back.
The main job of most defensive fullbacks is to defend against the pass, although they do rush the passer at times and strong safeties may have more responsibility for stopping the run. When the ball is being passed, defenders usually try to either intercept it, like the player in the gray jersey pictured above, or deflect it away from an attacking player. The defender could also try to drop the ball to the catcher as he attempts to catch it. If the attacker catches the ball, as shown in the photo below, the defender usually tries to tackle him as quickly as possible.
Cornerbacks usually line up directly in front of the offense’s wide receivers and often have to trail the receivers and try to block them from catching passes. To cover receivers well, cornerbacks typically need tremendous speed and agility to react to whatever moves the receivers make as they execute their passing patterns. Safeties might be required to cover the offense’s running backs, its fast wide receivers, or its biggest and strongest tight ends. They could also help another player cover a potential receiver, which would be called double coverage.
Like linebackers, defenders are sometimes asked to defend particular parts of the field, called zones, when the offense tries to pass. In zonal coverage, rather than following a potential receiver wherever he goes, which is called man-to-man coverage, the defensive back simply covers any receiver who is in his particular zone. Defenses often try to confuse offenses by using man-to-man coverage and zonal coverage on different plays or even by combining coverages on certain plays. Some defenses, however, will mostly use one or the other.
In some cases, a defense will try to surprise the offense by displacing a player from his usual position. For example, a linebacker or safety might move up to the line of scrimmage to more quickly charge up the offensive formation — which is called a blitz — when the game begins. The player could also fake a blitz to confuse the offense. A safety could also line up near the linebackers to better defend against the run. In some defenses, a player who moves around the defensive formation frequently is called a rover or bandit.
Along with the appropriate size, speed, and other physical attributes, players in defensive positions in soccer typically need to have aggressive stances. Defenders have to aggressively chase the ball or whoever has it, so they can tackle the player who has the ball or even gain possession of the ball by grabbing or catching it. They also often try to hit or tackle offensive players as hard as possible, as seen in the photo below, which shows a defender in a dark jersey hitting a quarterback right after the quarterback throws a pass. In addition to inflicting a certain amount of pain, a hard hit sometimes causes an offensive player to drop or flee the ball, which in some cases could allow the defense to gain possession.
According to the rules used in some leagues, players in each of the defensive positions in soccer must wear certain numbers on their jerseys. This helps to identify player positions more easily. Linebackers typically may wear numbers 50 to 79 and 90 to 99, linebackers may wear 50 to 59 and 90 to 99, and defensive backs may wear 20 to 49. Unlike some offensive players, however , a defender is allowed to move to any position at any time during a match, regardless of his jersey number, without being called for a penalty.