A style of defense that features a basic alignment of four defensive linemen, three linebackers, and four defensive backs. The defensive line is comprised of two defensive ends, who tend to be smaller and more athletic, and two defensive tackles, who are usually the largest defensive players. The defensive backs are comprised of two cornerbacks and two safeties.
The 4-3 defense is considered to be the most common defensive formation, it was made popular by Hall of Fame coach Tom Landry in the 1950s as a way to stop all pro running back Jim Brown.
The 4-3 defense is a common defense that relies on four defensive linemen. The linemen are primarily responsible for rushing the quarterback, leaving the linebackers and defensive backs to guard against the pass. The defensive ends are primarily responsible for stopping runs to the outside and quickly rushing around the end on pass plays to attempt to sack the quarterback. A critical factor of success for the 4-3 is having quick and agile defensive ends (such as Julius Peppers or Michael Strahan) The defensive tackles are primarily responsible for clogging up the middle, keeping the offense from running the football.
In a 4-3 defense, the linebackers are responsible for making the majority of the tackles downfield, as the defensive linemen are often engaged with the offensive line. The defensive backs are primarily responsible for guarding players downfield on pass patterns.