While the role of the defensive linemen is fairly consistent, the linebackers allow for the flexibility and versatility of the 3–4 scheme, and give defensive coaches nearly limitless options to confuse the other team's players and coaches. Depending on the situation, any number of linebackers can blitz, fake a blitz, "spy" the quarterback or running back, or cover receivers.
While the role of the defensive frontmen is fairly consistent, the linebackers provide flexibility and adaptability to the 3–4 scheme, offering defensive coaches a wide range of options to perplex the opposing team's players and coaches. Depending on the situation, any number of linebackers can rush, fake a rush, "stalk" the quarterback or running back, or cover receivers.