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Zone defense is a type of defense, used in team sports, which is the alternative to man-to-man defense; instead of each player guarding a corresponding player on the other team, each defensive player is given an area known as a "zone" to cover.
A zone defense can be used in virtually all sports where defensive players guard players on the other team.
Zone defense by sport 
A description of a zone defense corresponds to the number of players on the front of the zone (farthest from the goal) and works its way to the back of the zone. For example, a 2–3 zone is a zone defense in which two defenders are covering areas in the top of the zone (near the top of the key) while three defenders are covering areas near the baseline.
Other types of zone defense include:
- Match-up zone, a hybrid of man-to-man defense and zone defense where players apply man-to-man defense to whichever opposing player enters their area. John Chaney, former head coach of Temple University, is this defense's most famous proponent.
- Box-and-one in which four defenders are in a 2–2 zone and one defender guards a specific player on the offense. A variant of this is the triangle-and-two, in which three defenders are in a 2–1 zone and two defenders guard two specific offensive players. This scheme was invented by the late National Basketball Hall of Fame coach and former Temple University head coach Harry Litwack.
When a team plays a zone, the defenders must keep their hands up and in passing lanes and quickly adjust their positions as the ball and the offensive players move around. Teams that successfully play zone defenses are very vocal and effectively communicate where they, the ball, and their opponents are or will be.
Teams playing a zone occasionally try to "trap" the ball handler, an aggressive strategy designed to "double-team" the player with the ball. While this tactic may cause a turnover, it leaves one or more players on the offense undefended. The undefended player(s) are generally schemed to be on the opposite side of the court, away from the ball, so any attempt to pass the ball to them would result in the ball either traveling a long distance through the air or being relayed by a third offensive player, allowing the defense to recover. Good ball handlers can also try to "split" the trap by bringing the ball through the space in the middle of the two trapping defenders, creating an instant advantage for the offense.
Zone defenses were prohibited in the National Basketball Association prior to the 2001–2002 season. The NBA currently permits the use of zones; however, teams generally do not use them as a primary defensive strategy and no zone defense may feature an unguarded defender inside the free-throw lane (a violation of that results in a defensive three-second violation, which is a technical foul). The Dallas Mavericks are an example of an NBA team that regularly uses zone defenses; during the 2011 Playoffs, their zone defense was credited with slowing down offenses, forcing opposing players to recognize which defense they were playing. Zone defenses are more common in international, college, and youth competition.
There are several reasons for a team to use a zone defense. Some are listed below.
- The opposing team has a player or players too quick (in the case of guards) or too big (in the case of forwards or centers) for a man-to-man defense to be effective.
- Many zones pack defenders in the lane but allow the offensive team to take long-range shots. If the opponents are poor long-range shooters, a zone can be very effective.
- Unless trapping is involved, zone defenses typically do not involve aggressive pressure on the ball handler and allow the offensive team to pass the ball around the perimeter, leading to more time being used by the offensive team before a shot is attempted. Therefore, teams wanting to slow down the tempo of a game will often choose to play zone.
- A poor defensive player can often be "hidden" in a zone because teammates can more easily help if he or she is beaten.
- If players are in danger of fouling out (especially forwards or centers, who typically guard the lane), using a zone helps to take the pressure off them.
- Playing a zone is usually less tiring than playing man-to-man, so fatigued teams are more inclined to use zones.
- Some teams play a zone when the opponents inbound the ball under the basket to help prevent easy scores off of screen plays.
- Against teams with inexperienced guards, trapping zones can disrupt the offense and force turnovers.
Playing a zone entails some risks. Some are listed below.
- Zones tend to be weak on the perimeter, so they are not very effective against teams with good outside shooters.
- Zones have gaps (areas that are not well-covered by defenders) that can be exploited by teams that pass well or have guards capable of penetrating the zone.
- If a team is behind in the game, playing a zone is a poor strategy because zones usually allow the offense to take more time off the clock on each possession, which limits the time remaining for the losing team to reduce the lead. It also reduces the chances of stealing the ball from the attackers and attempting a quick counterstrike across open field. This is not always true, there are pressure zone defenses that can often cause quicker shots by the opponent or result in turnovers
- When a shot is attempted, it is often harder for players in a zone to find counterparts to box out for the rebound, which sometimes results in an offensive player getting an easy offensive rebound.
- Zone defenses require a commitment to scheming and practicing zone, both from coaches and players. While most players are familiar with playing zone defense, they are sometimes not expert in the nuances of the zone, such as spacing, which require familiarity and experience. When man-to-man teams switch to the zone defense, it is sometimes seen as a gimmick that is easily exploited by disciplined teams.
Attacking a zone defense 
While strategies for countering zone defenses vary and often depend on the strengths and weaknesses of both the offensive and defensive teams, there are some general principles that are typically used by offensive teams when facing a zone.
- Many popular zones (such as the 2–3 and 1–2–2) have a gap in the middle of the lane. Getting the ball in this area can be very effective because the defense is often forced to "collapse" on the ball handler, freeing up other players for open shots. To exploit this gap, many teams assign a forward to operate in the "high post" area near the free throw line to catch and distribute the ball. A forward in the high post area can also set screens on the players at the top of the zone to allow penetration by the guards.
- Quick passing is an important element of attacking any zone. The defense will shift as the ball moves, but if the offense can move the ball faster than the defense can react, open shots can result. Quick passing against a zone often leads to open three-point shots, and zone defenses are less effective against teams with good three-point shooters.
- Dribble penetration is very effective in breaking down a zone. If a guard can dribble into the gaps in the zone, multiple defenders must converge on the ball. The ball handler can then often pass to an open teammate for a shot. This strategy illustrates why preventing dribble penetration is important in playing an effective zone defense.
- Passing the ball to the interior of the zone can have similar effects as dribble penetration: as the defense collapses, a quick kick-out to the perimeter can result in either an open shot or continued quick passing, as the defense is now imbalanced.
- Short Corner: Attacking the "Short Corner", or baseline area behind the defense outside the lane, against a 2-3 zone puts the defense in rotation and opens up the mid post.
- Screening the backside of the zone: this opens up weakside shooters off a skip pass or ball rotation.
History of basketball zone defense 
Frank Lindley, Newton, KS High School basketball coach from 1914 to 1945, was among the first to use the zone defense and other innovations in the game and authored numerous books about basketball. He finished his career with a record of 594–118 and guided the Railroaders to ten state titles and seven second-place finishes.
American football 
Australian rules football 
The zone defence tactic, borrowed from basketball, was introduced into Australian football in the late 1980s by Robert Walls and revolutionized the game. It was used most effectively by Essendon Football Club coach Kevin Sheedy.
The tactic is used from the fullback kick in after a behind is scored. The side in opposition to the player kicking in places their forward players, including their full-forward and center half forward, in evenly spaced zones in the back 50-meter arc. This makes it easier for them to block leading players and forces the kick in to be more precise, in effect increasing the margin for error which can cause a turnover and another shot at goal. As a result, the best ways to break the zone are for the full-back to bomb it long (over 50 meters), often requiring a low percentage torpedo punt, or to play a short chipping game out of defense and then to switch play as opposition players break the zone. The latter has negated the effectiveness of the tactic since the 1990s.
Another kick-in technique is the huddle, often used before the zone, which involves all of the players from the opposition team to the player is kicking in huddling together and then breaking in different directions. The kicker typically aims in whichever direction that the designated target (typically the ruckman) runs in.
Netball is a sport similar to basketball with similar strategies and tactics employed, although with seven players per team. Zone defense is one of the main defensive strategies employed by teams, along with one-on-one defense. Common variants include center-court block, box-and-two zone, diamond-and-two zone, box-out zone and split-circle zone.
See also 
- Jane Woodlands (2006). The Netball Handbook. Human Kinetics. pp. 131–4. ISBN 0736062653.