See Defence - 1-3-1 Lute Olson.
The regular 1-3-1 does not get out into the passing lanes, unlike the extended 1-3-1.
X2 covers between the elbows extended, gets the ball out of the middle.
X5 plays between the ball and the basket, and defends dribble penetration.
Wings X3 and X4 are partners, take first pass (or a dribble entry), when one is out on the ball, the other protects weakside.
Point guard X1 is on the baseline, and covers corner to corner.
X4 takes the ball on the wing and forces baseline, X3 protects weakside.
X2 covers the high post (and a return pass to 1), X5 has the low post, and X1 is on the baseline.
There is strong ballside coverage, like a 2-3 zone.
Here X5 would box out high-post 5 on a shot.
Match-up option - if there is no attacker in the ballside corner, X1 has no one in his area, he can get weakside and tell X3 to push up (if 3 dribbles to the corner, X4 would stay with him).
If 5 is a dominant post player, X4 pressures the passer, X5 fronts, X3 supports from behind, X1 cheats in to provide baseline support, and X5-X1-X3 can triple team on a pass into 5.
X1 has the ball in a corner and takes away baseline.
X3 has a skip pass to 2.
X5 would trap dribble penetration by 4.
- denies a pass back to 3 (shown), which can force a long skip pass
- traps the corner with X1 (e.g. if 4 is a shooter), optionally X2 steps out to cut off a return pass to 3 and X3 rotates to the high post
- bumps X2 back and takes the high post (e.g. to cover a skip pass)
- drops and helps on the post if 5 is dominant.
Here X4 drops and helps on the post, X4-X5-X3 can triple team on a pass into 5.
Optionally tilt the zone to start in a 2-3 look, X3 takes a pass to 2 and X4 would take an entry pass to 3, keeping X1 on the baseline (could be used on a baseline inbounds).
X2 could cover 1 with the ball out top (a 1-1-3 look), then recover to the high post on a pass.