A cornerback (CB), also referred to as a corner, is a member of the defensive backfield or secondary in American and Canadian football. Cornerbacks cover receivers, to defend against pass offenses and make tackles. Other members of the defensive backfield include the safeties and occasionally linebackers. The cornerback position requires speed and agility. A cornerback's skillset typically requires proficiency in anticipating the quarterback, backpedaling, executing single and zone coverage, disrupting pass routes, block shedding, and tackling. Cornerbacks are among the fastest players on the field.
1 Overview 2 Zone coverage
2.1 Cover 1 2.2 Cover 2 2.3 Cover 3 2.4 Cover 4
3 Jamming the receiver 4 Single/man-to-man coverage
4.1 Loose man 4.2 Man up
5 See also 6 References
Overview The chief responsibility of the cornerback is to defend against the offense's pass. The rules of American professional football and American college football do not mandate starting position, movement, or coverage zones for any member of the defense. There are no "illegal defense" formations. Cornerbacks can be anywhere on the defensive side of the line of scrimmage at the start of play, although their proximity, formations, and strategies are outlined by the coaching staff or captain.
A cornerback for Trinity College rises to intercept an errant pass.
National Football League
When a cornerback is attempting to jam or funnel a receiver, he is trying to disrupt the receiver's route at the line of scrimmage. Many routes are precisely coordinated between the quarterback and the receiver, to the point that a quarterback may throw the ball without looking, knowing his receiver will be in an exact spot after a certain time. Jamming will disrupt the timing between the two, which provides the defense with extra time to sack the quarterback (sometimes called a "coverage sack"), or force an ill-timed throw that misses the target. In addition, a proper jam allows the safety or linebacker to provide stronger run support because he then has more time to drop back into zone coverage in the event of a pass. In other words, he has been granted more time by the corner to recover from his mistakes if he anticipates a run when in fact the play is a pass. Proper jamming technique requires the cornerback to use their legs, shoulder width apart. At the same time, the cornerback thrusts their arms forward into the receiver's chest to maximize power. When properly executed, a jam can knock a receiver off his feet. Jamming is only legal within five yards from the line of scrimmage. If the jam fails, the cornerback is usually flat footed and not in a suitable position to defend the mid to long-range passes. When this occurs, the safeties and linebackers usually cannot return to their zone obligations in time, especially if they were anticipating a run as the play began. In essence, the defense is unnecessarily "stretched" to its breaking point. Receivers who can effectively avoid the jam and stretch defenses are far more likely to create big play opportunities for the offense. Therefore, it is vital that a cornerback execute a proper funnel or jam to allow safeties and linebackers enough time to return to their zone responsibilities in the event of an unforeseen pass play. By working together and familiarizing where one's help may come from, a higher degree of confidence is established amongst the defensive secondary as a unit, with the end result translating into a much more formidable defense against both the run and pass. Single/man-to-man coverage In single or man to man coverage, the cornerback is responsible for a particular receiver assigned to him. As the play begins, the corner may either attempt to "jam" the receiver at the line, play a step or two off of him, or concede a few yards and play with a "cushion". Cushions can range from a yard or two, to forty yards in a "prevent defense" situation. Cushion is just how far off the defender plays away from the offensive player he is assigned to defend. When lining up in front of the receiver to "jam" him or playing just a few steps off, it is important that the corner keeps his body in front of the receiver's body. The easiest way for a corner to be in position is to line up slightly inside of the receiver and the ball, and keep his eyes looking between the receiver's hip and his knees. If a cornerback loses focus on his receiver, the receiver will run straight past him, and then it leads to corners having to use the cushion technique. Generally, cushions are smaller in single coverage and larger in zone coverage. Single coverage in the "red zone" – the area between the twenty-yard line and the goal line – is usually designed to prevent receivers from slanting towards the middle of the field. These types of routes are difficult to stop in the red zone because this area is usually congested with bodies colliding, crossing, and weaving in different directions. Although illegal, defenders are easily picked or screened by opposing receivers and sometimes by their own teammates; this is illegal yet difficult to enforce in short field, congested situations. To avoid this, it is often favorable for cornerbacks to either: "switch" assignments, where he will agree beforehand to trade assignments with one of his fellow defenders in the event that the receivers criss-cross as the play begins, or alternatively, a corner may instead line up very close to the receiver at the line of scrimmage to force or "jam" him toward the sideline (outside) without violating the 5-yard no-touch rule. Corners often refer to this second style of coverage as the "man under" technique. Single coverage, or man to man coverage usually employs relatively few techniques. However, they are often initially displayed to resemble one another as much as possible to disguise the true motives of the defense, and be interchangeable as well. Although terminology for single coverage can vary, a few generic terms have been included to establish a general understanding of cornerback philosophy and how his function relates to the rest of the defense. Loose man Loose man requires cornerbacks to play off the receiver with a five to ten yard cushion. He usually does not touch the receiver and tries to keep his head on a swivel in order to move in whatever direction the receiver decides to shape his route. Typically with loose man coverage, the cornerback has little or no help from the safety in defending against the receiver. This defense is used to discourage deeper passes, but often allows short yardage passes. A loose-man defense looks to create confusion for the quarterback by using blitzes. The idea is to disrupt the coordination necessary for short routes, which leads to drops or poorly thrown passes stalling the drive. However, accurate quarterbacks with a quick release of football can exploit this and routinely make 3 to 5 yard completions to receivers. Man up By far the most challenging, the man up technique grants the wide receiver a relatively free release as the corner shadows him stride for stride everywhere he goes. The cornerback's objective here is to position himself between the quarterback and the receiver, without knowing where the receiver is going. As the ball is snapped the corner will initially ignore the quarterback, turn and run with the receiver and hope the ball does not drop out of the sky before he can react to it. Corners must also hope the receiver does not change directions when it is time to sneak a peek at the quarterback in effort to discover where the ball is. A wet field makes this coverage extremely difficult. In addition, a perfect throw is hard, if not impossible, to stop. This coverage is usually reserved for the elite cornerback with superb coverage skills. See also
^ A Brief History of the Game. ^ "NFL Rules Digest: Position of Players at Snap". Retrieved January 7, 2010. ^ "2009-10 NCAA Football Rules and Interpretations" (PDF). Retrieved January 7, 2010. [dead link]
Kelly, Danny (June 6, 2011)) "The 4-3 Under Defense: Coverage Schemes" SB Nation Thurmond, Chris (January 27, 2012). "Rice University Cornerbacks Coach". telephone interview.
Offense (Skill position)
Linemen Guard, Tackle, Center Linemen Tackle, End Kicking players Placekicker, Punter, Kickoff specialist
Backs Halfback/Tailback (Triple-threat), Fullback, H-back, Wingback Backs Cornerback, Safety, Halfback, Nickelback, Dimeback Returning Punt returner, Kick returner, Jammer
Formations (List) — Nomenclature — Strategy
v t e
American–Canadian comparison Burnside rules Glossary
Arena Indoor 9-man 8-man 6-man Flag Touch Street/Backyard Powderpuff Wheelchair Rules of gridiron football codes
Levels of play
Pop Warner AYF
Varsity Junior varsity
Hash marks Goal line Sidelines
Line of scrimmage
End zone Red zone Neutral zone Coffin corner Flat Gap Hole Pocket
Touchdown One-point conversion Two-point conversion Field goal Safety Single (rouge)
Fumble Interception Muffed punt Turnover on downs
First down Three-and-out Fourth down conversion Dead ball
Timeout Kneel Spike Time warnings
3 min. 2 min. 1 min.
Clock management Running out the clock Untimed play Garbage time
Total quarterback rating
Yards after catch
Yards from scrimmage
Two-a-days Oklahoma drill Three-cone drill Film session
Official (American, Canadian) Chain crew Penalty Penalty flag Instant replay
Running up the score