2X2 and X3 get in the passing lanes, facing the ball (X1 talks to X2, X5 talks to X3).
X5 covers the high post, X1 covers the low post (and has to close out on a pass to the corner), X4 defends low weakside.
X5 defends dribble penetration, along with X3 and X2. X3 can help on a pass to the high post.
Dean Smith 52 zone - on dribble penetration, X5 and X3 fake at 1, X2 is designated to stop the dribble and stay with him. For good rebounding coverage in this offence, X3 must move quickly to rebound on the weakside.
DeChellis 1-3-1 - defenders have to have "bounce", they can't play flat-footed. X4 has his ballside foot up in a boxer stance.
Bennett 1-3-1 - X3 and X2 pinch the seam on dribble penetration, with help from X5 if needed. On a pass to the high post, X3 double-teams with X5.
Blackford - X5 plays between the ball and the basket, with his toes on the 3-point line, and doesn't worry about what's behind him. If 1 splits the X2-X3 box, X5 comes up to stop penetration, the only time they have three guys on the ball. If 1 passes to the high post, X1 or X4 have to cover until X5 turns and gets back in the play.
(Here X4 could help on the high post.)
Felton - X5 is always between the ball and rim, but adjusts if there is a high post, using his length to put a hand in front of 5 while facing the ball. If 1 drives middle, X3 and X2 attack him then run away to take away passes as X5 steps up to stop 1 at the 3-point line. X3 takes away the high post if there is one, otherwise takes away 3.
DeChellis - X5 keeps the ball out of the high post.
Greenberg - X5 keeps the ball out of the high post one full step beyond the arc, denies from the side, goes behind on a guard-to-guard pass.
Aldo Corno 1-3-1 - X5 fronts the high post, and is ready to slide down and front the low post. Don't ever let the ball enter the high post, it's the most dangerous spot on the floor.
Coach Mac - X5 stays between the ball and the rim, and keeps the ball out of the post, fronting to deny and help on dribble penetration. When X5 steps out to stop dribble penetration (ending up with three players on the ball), he is no longer responsible for the high post. X1 and the weakside wing pinch in to prevent passes into the paint. Any time the ball is passed into the high post, double with X3 and X5, X1 and the weakside wing guard the blocks.