Conventional wisdom tells us the most important part of an offense is the quarterback position. Looking at the defense, the opinion varies. Many pundits will tell you that a pass rusher is of the utmost importance. In ESPN's Defensive Player Power Rankings, a whopping 7 of the 16 vote getters were primarily outside pass rushers. However, the 3-4 defense is largely considered to hinge around the play of the Nose Tackle, due to the outward effect on the rest of the front seven. With that in mind, which position holds the most water?
There's split camps on this issue. Some will argue that without the widebodies, the rushers can't do what they do effectively. Others will argue the rushers are more impactful to the overall outcome of the game. Let's dissect these arguments.
Dominant - The player is an impenetrable fortress in the middle of the field, an immovable brick wall. The player holds double teams and shoves them into the backfield, creating rippling mismatches throughout the down linemen and linebackers. Gaps are sealed without effort, blitzes are far more effective, and the interior run game is largely inefficient. These are incredibly rare players, as the massive size, strength, and speed combination is not one that comes into the league readily, but superior football instincts are not required. Their presence alone raises the rest of the front seven's ability immensely.
Nonexistent - The player can be shoved into the second level by a single blocker. Repeatedly, the player will allow blockers to get downfield, creating positive mismatches for the offense's blocking scheme. Gaps are wide open, allowing running backs and running quarterbacks the ability to freely roam 5-6 yards beyond the line of scrimmage. Blitzes get picked up easily, due to the extra blockers available to cover the blitzer. Their presence alone will not kill the entire defense, but will make for long drives and easy first down pick ups along the way.
Pros: Can raise the level of every player around them, can completely take away one facet of the offense, allows for more freedom on stunts/blitzes, not required to have elite football instincts
Cons: Can also lower the level of every player around them, very hard to find a dominant build for player at the position, usually only contributes on two downs
Dominant - The player is a frightening force on one side of the field. The player will blow by defenders to get to the ball, creating losses of yardage without the help of those players around them. Can drop into coverage against a running back or tight end, taking away a short pass while allowing more traditional pass defenders to play a deeper route. Size, speed, and strength of these players relatively easy to find compared to most positions, but superior football instincts are required to identify the play and determine the course of action. Their presence usually has a greater positive impact on the game (i.e. forced fumbles, sacks, interceptions) than most in the front seven.
Nonexistent - The player can regularly be blocked out of harm's way. They can be beaten with minimal footwork and handfighting, allowing lesser offensive linemen to single-team the player. The player likely does not have the ability to hold his ground against the run, nor drop into coverage, which requires the second level of linebackers to play closer to the line of scrimmage to compensate, creating holes in the defense. They can allow the outside edge of the line to be achieved by running backs and running quarterbacks, usually leaving the superior tacklers of the team chasing the ball carrier. They also allow the quarterback to pick apart the defense with the passing game, allowing receivers to run longer, more elaborate routes, and allowing the quarterback to get into his full, uninterrupted motion. Therefore, the player's negative influence puts more pressure on the second and third levels of the defense.
Pros: Doesn't require an elite supporting cast to be dominant, potential for more game-changing plays, typical build to find in college, shortcomings can be overcome by a good to great pass defense
Cons: Hard to find special blend of player with elite instincts, can put run defense and pass defense in a huge bind by giving up the flat, can make an average pass defense look even worse
Looking at the Chiefs, the team is lucky enough to have a top defensive player at the weakside outside linebacker position in Tamba Hali, so it's easy to see the positive impact that position can hold. In the same defense, one can see a mediocre strongside outside linebacker rotation and a mediocre nose tackle rotation, so one can see the shortcomings on both sides. Giving it some thought, how much would it affect this defense with a dominant nose tackle and mediocre outside linebacker? How about vice versa? If only one can be chosen, which one would you rather have?