Who are Defensive Backs? They are the players that make up in the defensive backfield. This is the third line of defense, yet it is also called the secondary and to further complicate matters, they aren’t always lined up on the third “line.” The defensive backs typically consist of two safeties and two cornerbacks and in some instances a fifth player (nickel-back) and a sixth player (dime-back). For our purposes we are going to refer to the traditional scheme with just four defensive backs.
Cornerbacks. They are typically the fastest players on the defense because they must cover the most ground. A cornerback needs to have quick and loose hips. I’m not sure how they judge this, but it is important to have those assets in order to change direction quickly. He also needs to have good recovery speed (see below). In Cover-2 (a type of zone coverage defense) the corners provide outside run support.
Safeties. The two safeties are further differentiated in that there is one free safety and one strong safety. In reality, each player may act as both strong and free and they will periodically switch roles depending on what side of the field (left or right) their opponent’s tight end lines up on.
Strong Side. From a defensive point of view, in the most standard formation, whichever side the tight end lines up on is considered the strength of the running formation. And a defense will often adjust their formation so that the strong safety and the strong side linebacker line up on that “strong” side. However, it is not always that simple (see “How defensive players read the offense” in the Training Camp for Defensive Backs article).
Strong Safety—while the strong and free safeties must be able to play both roles, they are still different positions. And the strong safety is typically the best of the defensive backs when it comes to stopping the run. Even though the cornerbacks will have run defense duties as described above, the strong safety may switch with the corner on a specific play because of his run stopping abilities. This happens in Cover-3.
What does a defensive back do? In addition to any run defense duties he may have, the defensive backs are the ones ultimately responsible for defending against the pass and statistically take the credit or fault for how another team’s passing offense does against them. In order to do this, each player needs to know his particular assignment on a play, follow the technical progressions (meaning that as the play progresses, he is able to figure out and anticipate where is it going), close the cushion and defend the ball.
