<P> Zone defenses were prohibited in the National Basketball Association prior to the 2001 -- 2002 season . The NBA now permits the use of zones , though most teams do n't use them as a primary defensive strategy , and defenses featuring an unguarded defender inside the free throw lane are now disallowed ( a violation that results in a defensive three - second violation , which is a technical foul that was also implemented in the 2001 -- 2002 season ) . 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 determine which defense they were playing . Zone defenses are more common in international , college , and youth competition because the defensive three - second violation makes it difficult for NBA teams to play zone , since such defenses usually position a player in the middle of the key to stop penetration . </P>
<P> Zone defenses were prohibited in the National Basketball Association prior to the 2001 -- 2002 season . The NBA now permits the use of zones , though most teams do n't use them as a primary defensive strategy , and defenses featuring an unguarded defender inside the free throw lane are now disallowed ( a violation that results in a defensive three - second violation , which is a technical foul that was also implemented in the 2001 -- 2002 season ) . 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 determine which defense they were playing . Zone defenses are more common in international , college , and youth competition because the defensive three - second violation makes it difficult for NBA teams to play zone , since such defenses usually position a player in the middle of the key to stop penetration . </P>
when did zone defense start in the nba
when did zone defense start in the nba
2001 -- 2002 season
2001 -- 2002 season