Football Secondary

You may have heard a football announcer describing a defensive breakdown in the secondary that allowed a costly score. What is the secondary, and what does it do? Keep reading to learn all about the positions and roles of the defensive players in the secondary.
What is the Secondary in Football?
The secondary in football is a group of defensive backs that play in the backfield to provide deep coverage and prevent big plays. The secondary plays farthest from the line of scrimmage and provides deep coverage.
Football defensive formations are split into three levels: the defensive line, the linebackers, and the secondary. The defensive line includes the defensive tackles and defensive ends, and plays on the line of scrimmage. Linebackers play a few yards back from the line of scrimmage. Both of these levels play closer to the line of scrimmage than the secondary, who are located in the backfield.
Football Secondary
The secondary in football is a group of defensive backs on defense:
- Cornerback (CB)
- Free Safety (FS)
- Strong Safety (SS)
The secondary is positioned in the defensive backfield or at the line of scrimmage at the start of every down.
The secondary is responsible for:
- Preventing a score from the offense
- Countering receivers on the offense
- Sacking the quarterback or tackling the ball carrier
- Forcing turnovers
Secondary Positions
The major secondary positions are: Cornerback (C), Free Safety (FS), and Strong Safety (SS). Read on to learn about defensive backs as a whole, the defensive backfield, and all three of these secondary positions.
Defensive Back

A defensive back is another name for a player in the secondary. Defensive backs can refer to cornerbacks, free safeties, or strong safeties.
There are special names for defenses that require extra defensive backs: five DBs is a “nickel” scheme, while a “dime” defense adds a sixth defensive back. These extra defenders are known as the nickelback and dimeback, respectively.
Defensive Backfield

The defensive backfield is the area on the football field behind the line of scrimmage. The defensive backs of the secondary are located in the defensive backfield.
Cornerback

The cornerback is a defensive back who protects against the pass and counters wide receivers on the offense. Cornerbacks must follow receivers that run routes on the field to prevent a pass from being caught. Some schemes require a cornerback to blitz the quarterback. Cornerbacks must be fast and excellent tacklers.
Strong Safety

The strong safety is a defensive back that stands on the strong side of the field opposite the tight end. A strong safety will protect against the pass and is a final line of defense against run plays, which often occur on the strong side.
Free Safety

The free safety is a defensive back that stands on the weak side of the field opposite the strong safety. This player is usually the last line of defense. A free safety will often protect against deep passes, which tend to be thrown to the weak side of the field.
Strong Safety vs. Free Safety
There are three major differences between strong and free safeties, and these are:
- Side: Strong safeties stand on the strong side of the field, which is the side where the offensive tight end (TE) lines up.
- Size and physique: Strong safeties are generally larger and bulkier than free safeties, as their position on the strong side means that they tend to do more blocking. Free safeties tend to be smaller and more agile in order to aid in pass coverage.
- Speed: Free safeties tend to be slightly faster than strong safeties on average, as they are more often tasked with covering long passes.
Football Strong Side

The strong side of the field is the side that the tight end lines up on. It's used for play design in football. The strong safety stands on the strong side of the field. The main reason it is called the strong side is that the tight end’s position there creates a stronger offensive presence on this side, meaning that there are more offensive blockers capable of opening up a path for running backs and wide receivers. This is why strong safeties tend to be larger and stronger than free safeties, as they must be able to endure heavy blocks and knock out offensive linemen in order to stop a run play or a short pass.
FAQ
What is the CB position in football?
The CB position in football is the cornerback. A member of the secondary defense, a cornerback is responsible for covering wide receivers and providing deep coverage against the run. Occasionally, a cornerback will be tasked with blitzing the quarterback. There are typically between two and four cornerbacks in a defensive scheme.
What does the secondary mean in football?
The secondary in football is the level of the defensive formation that plays farthest from the line of scrimmage, providing deep coverage against runs and passes. The other two levels of the defense are the defensive line and the linebackers. The player positions that typically make up the secondary include cornerbacks, a strong safety, and a free safety.
What is the difference between a defensive back and a cornerback?
A defensive back is a term for any member of the secondary defense, while a cornerback is a specific position within the secondary. Strong safeties, free safeties, and cornerbacks can all play roles in the secondary and can all be referred to as defensive backs. The specific role of cornerbacks includes covering wide receivers and preventing deep runs.