3.8: Sets and Systems

Chapter 3: Offense

The alignment a team starts from and the script it runs: Horns, Zipper, the set play as a concept, and the named sets and plays heard that have no entry yet.

New terms introduced (3): Horns, Set play, Zipper. Diagrams: 2.

Five lectures of actions have treated each action as a thing on its own. A team does not run one action; it starts from a shape and runs a sequence. The shape is the set, and the sequence is the play. This lecture is about both, and about the difference, because the two words are used interchangeably on a broadcast and mean different things.

A set is where the five players stand when the possession starts: Horns with two bigs at the elbows, 5-out with everyone outside the arc, a box with four players in a square. It carries no instructions. What it does is decide which actions are available and which help is far away, and a good set makes several different plays look identical for the first two seconds.

A set play is the script: this screen, then that cut, then this pass, run to get one shot for one player. It is the opposite of the motion offense and flow of lecture 3.11, which give players rules instead of a script.

Section 1 is Horns, the most common set in the sport and the clearest example of what a set is for. Section 2 is Zipper, an action named for the cut it contains, which teams run out of several sets. Section 3 is the set play as a concept: why teams run them, when, and what they cost. Section 4 names the sets and plays heard on a broadcast for which this site has a description but not an entry.

1 Horns

Horns is the point guard at the top with the ball, two bigs at the two elbows, and two shooters in the two corners, as in Figure 1. Every glossary that names it names the same shape. What it buys is stated by looking at the floor: the paint is empty, so any drive meets nobody; the two bigs are both a pass away from the ball and both able to screen it; the two shooters are in the corners, the furthest a help defender can be from the rim and still be guarding someone who can shoot.

The Horns alignment. The point guard 1 is at the top of the key with the ball. Two bigs, 4 and 5, stand at the two elbows, and two shooters, 2 and 3, stand in the two corners. Each attacker has a defender beside him, and the two bigs' defenders stand just outside the lane lines, so the paint between them is empty, and a label says so. A title across the top reads Horns: 1 up, bigs at the elbows, shooters in the corners.
Figure 1: Horns. The ball at the top, two bigs at the elbows, two shooters in the corners, the paint empty. This is the alignment, not a play; a dozen plays start from it.

From that shape, several plays start the same way and end differently. Figure 2 shows one of them: the ball-handler takes a ball screen from one big and drives off it, while the other big, instead of rolling, sets a flare screen for the corner shooter lifting to the wing, and the skip pass goes there. The first two seconds are identical to a plain pick-and-roll, and the defense has to guard both.

One play from Horns. The guard 1 at the top with the ball dribbles right, off a ball screen from 5, who has stepped up from the right elbow; the screen bar sits between 5 and the guard's defender, and a label just under it reads ball screen. 5 rolls down the lane toward the rim, and his own defender waits in the paint. 4, the big from the left elbow, has stepped out toward the left corner and sets a screen, labeled flare, on the defender of the left-corner shooter 3, who cuts up the sideline to the left wing, labeled shooter lifts. A dashed pass arrow, labeled skip, runs from where the dribble ends on the right side across the floor and ends just short of the wing, ahead of 3. The other shooter 2 stays in the right corner with his defender.
Figure 2: One play from Horns. The handler takes the ball screen from the right elbow and drives right; the left-elbow big flares for the shooter lifting from the corner; the skip pass goes to the wing while the screener rolls.
Setup
The handler at the top with the ball. Two bigs at the elbows, facing him. Two shooters in the corners. The paint empty.
Trigger
The handler picks a side: he dribbles at one elbow, which turns that big into a screener and the other into an off-ball threat.
Read
The handler reads which big’s defender commits. If the screener’s defender plays the ball, the screener rolls into an empty paint. If the defense switches, the rolling big has a mismatch and the early seal of lecture 3.7 is on. If the weak-side defenders shade toward the ball screen, the second big’s flare or pin-down for a corner shooter is open, and the pass is a skip. If the corners’ defenders never leave, the ball screen is two-on-two with the whole paint to work in.
Payoff
A pick-and-roll with no help in the lane and a weak-side action running at the same time, from a shape that makes several plays look the same at the start.
Beaten by
Switching everything, which takes away the screens and concedes the mismatches; or a big who plays the ball screen at the level while the low man tags the roller. Lecture 4.3, lecture 4.4 and lecture 4.5.
Action 1: Horns: a shape that empties the paint and puts two screeners a pass away.

2 Zipper

The zipper is an action rather than a set: a player cuts from the block straight up the lane line off a screen and catches at the slot, as in Figure 3. It is a pin-down with the cut made vertically along the lane line rather than out toward the wing, and what it buys is a catch at the top with the whole floor in front of the catcher rather than a catch on the wing with half of it. Teams run it as the first action of a possession, to get the ball into the hands of a guard who did not bring it up, and as an entry into a ball screen: the catcher at the slot is immediately in position for the big to screen for him.

The ball is at the top. A guard starts on the right block with his defender just above him on the lane side. A big stands just inside the lane line above them, below the elbow, facing the baseline, with a screen bar below him, labeled big's screen. The guard cuts straight up the lane line past the big and the bar, from the block to the right slot, and catches the pass at the slot, labeled catch at the slot. His defender is below the screen, behind the big.
Figure 3: Zipper. The guard cuts from the block straight up the lane line off the big’s screen and catches at the slot, with the floor in front of him.
Setup
The ball at the top or the wing. A guard on the block. A big on the lane line above him, facing the baseline. The weak side spaced.
Trigger
The screen is set on the lane line; the guard cuts.
Read
The four reads of lecture 3.5 apply: chased over, curl to the rim; defender under, catch at the slot and shoot; caught, straight up and catch; jumped above, back cut. The screener reads his own defender: if he helps on the cut, slip to the rim.
Payoff
A guard catching at the slot with the floor in front of him, usually straight into a ball screen from the man who just screened for him.
Beaten by
Top-locking the cutter so he cannot come up the lane line, conceding the back cut; or switching the screen. Lecture 4.4 and lecture 4.5.
Action 2: Zipper: up the lane line to the slot, with the floor in front.

3 The set play

A set play is a script. Its value is that five players know what is coming and the defense does not, and its cost is that it takes three or four seconds to set up, during which the defense is getting organized. That trade decides when teams run them: after a timeout, when the defense cannot have prepared for this one; at the start of a possession against a set defense, when nothing is available anyway; for a specific player who needs a specific shot; and at the end of a quarter or a game, when there is one possession and no second chance. The rest of the time most teams would rather play with rules, which is lecture 3.11.

Setup
A named alignment (Horns, box, 1-4, double stack) and five players who know the script.
Trigger
A call, a hand signal, or a dead ball. An ATO is the standard case, taught in lecture 3.12.
Read
A set play is not read-free. Every good one has an option at each beat: if the first cutter is covered, the second screen is the answer; if the defense switches, the mismatch is the answer. What distinguishes it from motion is that the options are enumerated in advance rather than derived from rules.
Payoff
One specific shot for one specific player against a defense that has not seen this sequence today.
Beaten by
A defense that has scouted the set and jumps the first action, which is why teams run several plays that look identical for two seconds; and by the clock, since a play that takes four seconds to set up leaves fewer to improvise with if it fails.
Action 3: The set play: a script, worth its cost when the defense cannot have prepared for it.

4 Names heard for which there is no entry yet

The sets and plays below are named by one publisher, or are one team’s call for an action this site already teaches under another name. Each has a description here and no entry; the rule and the dated diff are in data/sources/glossary_diff_2026-09-21.md.

  • Horns twist. A Horns play in which the two elbow bigs screen for each other before one of them screens the ball, so the ball screen arrives from the side the defense did not expect.
  • 1-4 set, box set, double stack. Three more alignments. The 1-4 has both bigs at the elbows and both wings in the corners, which flattens the defense and opens the lane for back cuts; the box is four players in a square at the elbows and blocks; the double stack puts two players on each block. Box and stack are taught in lecture 3.12, where they are used most.
  • Miami. A combination in which the ball is entered to the high post, the point guard sets a shuffle screen, and the shuffle screener then takes a handoff from the high post.
  • Corner offense. An alignment with three players on the strong side (a big at the elbow, a guard in the corner and one on the wing), a big at the weak-side elbow, and a forward near the weak-side slot.
  • Bulldog, Celtic, Cyclone, Jazz, Phoenix. Five more calls named for programs and franchises, each one a team’s single word for a short string of actions this site already teaches one at a time. Bulldog sets a ball screen and a cross screen at the same moment, so the defense has two screens to talk through at once. Celtic runs a UCLA cut straight into a side ball screen, and Jazz starts from that same UCLA cut and follows it with a screen set for the man who just screened, the cutter taking part in it. Cyclone is a cross screen straight into a zipper screen. Phoenix strings a shuffle screen, a flare screen and a dribble handoff together, with the post player deciding which of the three the ball comes out of. In each case the name is a call and not a concept: it says whose playbook the sequence came from, and the pieces inside it are the actions of the earlier lectures.
  • Team-named plays. The plays pages of the coaching sites are full of calls named for teams and colleges. Those are one team’s name for a sequence, not vocabulary, and they are out of scope for this site by rule.

The idea to carry into lecture 3.9 is that a set play ends. The offenses in the next lecture do not: they are continuities, which return to their own starting shape and can be run until the shot clock ends.