Match-up zone defense is a type of defense used in the game of basketball. It is commonly referred to as a "combination" defense, as it combines certain aspects of man-to-man defense and zone defense.
With the match-up zone defense, the on-ball defender will play tight as if he was playing man-to-man. At the same time, the zone away from the ball will resemble "help-side" man-to-man defense. This creates one of the advantages for the match-up zone, as it may confuse the opponent as to what defense you are actually playing. The match-up zone also resembles a "switching man-to-man" defense, where the big men stay down low in the post and the guards stay around the perimeter. When asked to describe Chaney's match-up zone, Saint Joseph's Hawks coach Phil Martelli replied: "In college basketball, there's the Pete Carril Princeton offense, the John Chaney Match up Zone defense, then everything else. Those are the only two truly unique syles designed and being used today."