Zone blocking

Zone blocking is a technique in American football that is a simple and effective scheme for creating lanes for running plays.

In a zone blocking scheme, fleet-footedness and athletic ability trump size as desirable qualities in offensive linemen. Coordination and technique matter more than muscle in implementing a successful scheme because defensive linemen are often double-teamed at the point of attack. In this blocking scheme which takes much from the Veer blocking system, creating movement on the defensive line is more important than opening a specific hole in the defense.

Team support
One of the simplest reasons many teams have incorporated zone blocking in their offenses is that zone blocking rules do not change based on the defensive front. In a "man block" system, blockers are paired with defenders according to certain rules to create a running lane. If the defensive front changes, or if the defense stunts or blitzes, the blocking rules may change. This requires learning multiple rules for the same play. Zone blocking uses very consistent rules that do not change according to the defensive front.

Some teams base their entire offense on it, including the NFL's Washington Redskins, Indianapolis Colts, Oakland Raiders, Houston Texans, Seattle Seahawks, Kansas City Chiefs and Green Bay Packers. Adopting a variation of this scheme's core principles, the West Virginia Mountaineers rely on it in the run-based spread offense, devised by former head coach Rich Rodriguez and former offensive line coach Rick Trickett, that they have used even after their departure. The University of Iowa under head coach Kirk Ferentz, a former NFL offensive line coach, utilizes zone blocking and the inside/outside stretch play as the basis for their offense. The University of Michigan also started using zone blocking under head coach Lloyd Carr in the 2006 season, and had continued to do so under his successor, Rodriguez.

The Carolina Panthers made the switch to zone blocking under offensive coordinator Jeff Davidson for the 2007 season. They had previously employed a man-blocking scheme for a downhill running attack under coordinator Dan Henning, but during the 2006 season, the team's undersized linemen were consistently overpowered by opposing defensive linemen. The power running game became stagnant, and especially ineffective in goal-line/short yardage situations, thus resulting in Henning's firing and the switch to zone blocking. Thanks in part to the new blocking scheme they implemented, the Panthers saw their 2008 campaign characterized by the running of DeAngelo Williams and Jonathan Stewart to great effect, gaining them play off status. That season also saw the emergence of rookie Steve Slaton with the Houston Texans under their new Alex Gibbs-designed zone blocking scheme.

Linemen techniques
Using a running back out of the backfield, zone plays are usually categorized into three types: Inside Zone (IZ), Outside Zone (OZ) and Stretch. These types describe the initial landmark of the ball carrier. A common approach is: Inside the tackles for IZ, just outside the tackle for OZ and just inside the last offensive player for the stretch.

For each type of zone there are many different blocking schemes available: - The most basic form asks the offensive linemen to identify whether he is covered or uncovered. If the latter is the case, he is asked to help play-side on a double team by using wide lateral steps or even bucket steps. The resulting double team then reacts to the movement of the linemen as well as the movement of the linebacker. The initial movement of the double teams helps to equalize defensive talent and creates cutback lanes.

- Another scheme asks the offensive linemen to imagine a "railroad track" parallel to the running backs path and block everything they find on their way. This could be a linebacker, but also a slanting defensive linemen from somewhere else.

- Starting from either inside or outside, some offensive lines always pair two on one and use a fullback to block the remaining defender outside. This makes it necessary for the offensive linemen to use a variety of line-splits and steps.

- By using a counting system some offenses believe to eliminate unfavorable matchups that can be the result of unusual defensive alignment. This is often used in conjunction with other schemes.

- For the outside varieties of the zone play a scheme that is called Pin&Pull has had great success. The linemen do not step play-side, but try to "pin" a backside defensive linemen, while the next backside offensive linemen pulls around the block and up to a track to the second level. Today every NFL team uses some form of zone blocking but not all of them rely on it entirely.

Cut blocking controversies
The linemen of some teams that use zone blocking schemes have been criticized for their penchant for cut blocking the knees of defenders, sometimes away from the play. Cut blocks are illegal when a defensive player is engaged by another offensive player. Although some consider the technique unsportsmanlike because of the risk of serious injury, when taught and applied correctly it is a very effective tactic. In fact, some defensive players employ the technique to eliminate blockers so other defenders can make the tackle.

Sophisticated schemes
Zone blocking schemes frequently employ deception. For example, plays may be called in which blitzing defensive linemen and linebackers are permitted to rush into areas of the offensive backfield that are unimportant in the play called by the offense. Meanwhile, the offensive linemen who vacated the unimportant area migrate to the point of attack, blocking material defensive players.

Other Players Role
Players other than offensive linemen may enhance the success of a zone blocking scheme. For example, in a run-based spread attack like West Virginia's the primary responsibility of receivers is less to catch passes than to execute downfield blocks, springing the ball carrier and extending the run.