Defensive formation - 4-3 defense

"This base defense consists of four defensive linemen, three linebackers, and four defensive backs (two safeties, two corners). Against two-receiver offensive sets, this formation is effective against the run and the pass. In the original 4–3, defensive tackles would line up opposite the offensive guards, and defensive ends on the outside shoulders of the offensive tackles. On passing downs, the Mike (middle linebacker) is often responsible to cover any running backs, the Sam (strong-side linebacker) covers the Tight End, and the Will (weak-side linebacker) either covers a back or blitzes in an attempt to sack the quarterback. Though first used as a base defense by the New York Giants in 1956, plenty of teams experimented with it during the 1950s, and thus there are multiple claimed inventors of this defense. There are several different variations of the 4–3 defense such as the 4-3 under defense, 4-3 over defense, 4-3 umbrella defense, 4-3 swim defense, and 4-3 slide defense." [List of formations in American football. Wikipedia]
This example diagram was redesigned from the Wikimedia Commons file: 4-3 green.svg.
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The American football positions diagram example "Defensive Formation - 4-3 defense" was created using the ConceptDraw PRO diagramming and vector drawing software extended with the Football solution from the Sport area of ConceptDraw Solution Park.

"In American football, each team has eleven players on the field at one time. The specific role that a player takes on the field is called their position. Under the modern rules of American football, teams are allowed unlimited substitutions, that is teams may change any number of players after any play. This has resulted in the development of three "platoons" of players, the offense (the team with the ball, who is trying to score), the defense (the team trying to prevent the other team from scoring, and to take the ball from them), and the special teams (who play in kicking situations). Within those platoons, various specific positions exist depending on what the player's main job is." [American football positions. Wikipedia]
The American football positions diagram example "3-4 Defense" was created using the ConceptDraw PRO diagramming and vector drawing software extended with the Football solution from the Sport area of ConceptDraw Solution Park.

"In American football, the dime defense is a defensive alignment that uses six defensive backs. It is usually employed in obvious passing situations.
The formation usually consists of six defensive backs, usually two safeties and four cornerbacks, and has either four down linemen and one linebacker, or three down linemen and two linebackers. This formation is to prevent the offense from completing a medium to long range pass play. This may be because the offense's running game is inefficient, time is an issue, or they need a long pass for a first down. It is also used against teams whose pass to run ratio predominately favors pass . The formation, however, is vulnerable to running plays as the formation is missing two linebackers, or a linebacker and a down lineman. A dime defense differs from the nickel in that it adds a sixth defensive back to the secondary. This sixth defensive back is called a "dimeback" (D). The defense gets its name because a dime is the next step up in US coin currency from a nickel. There are also 'quarter" and "half-dollar" formations (each protecting against progressively deeper thrown and more likely pass attempts)." [Dime defense. Wikipedia]
The American football positions diagram example "Dime defense" was created using the ConceptDraw PRO diagramming and vector drawing software extended with the Football solution from the Sport area of ConceptDraw Solution Park.