I thought there might be some interest in a discussion about different offensive sets so I decided to write a thread about the triangle. In the future I might discuss other offenses around the league if there's any interest.
Let's start with some underlying premises of the triangle offense.
First, it emphasizes spacing and ball movement in order to penetrate the defense. This differs from typical offensive schemes because it values dribble penetration a lot less. Rather than rely upon a perimeter player to pierce the defense, it focuses on off-ball movement and post players to create passing lanes in the teeth of the defense.
Second, for the most part it's a read-and-react defense. Most modern versions of the offense (Lakers/Timberwolves) incorporate set plays within the triangle offense framework but the majority of the offense is based on reading the court and finding the best options available. For this reason, every player on the court is assumed to be a legitimate offensive threat.
Forming the Triangle
Like most offenses, the ball is brought up the court by two players. One player (usually the PG) dribbles the ball up the court while another player is slightly behind parallel to provide relief from full court pressure and traps. This idea of having a second player to relieve pressure is called the lag principle. These two players will eventually move up the court with the off-ball player filling the empty wing position and the ballhandler filling the defensive balance position.
We'll start by using a picture of the typical halfcourt set.
In this picture we see the PG with the ball, the SG and SF on the wings, the PF and C in the low post. This is how most offensive sets begin before a play is called. The triangle usually begins the same. Notice the hash marks on the left and right top corners? That is roughly where the triangle offense begins. This is called the moment of truth. It is at this point when the ball is being carried up the court that the ballhandler (usually the PG) will ideally make his initial pass to either wing - initiating the start of the triangle offense. This pass is called the number 1 pass.
Take note of where the PG is right now, the PG is in what is called defensive balance. This position is intended to gather long offensive rebounds, serve as a passing option to reverse the ball, and head the defense down the court on defensive rebounds. This position is also available for top of the key 3pters. This spot becomes important when we discuss spacing later on.
Let's assume that the PG decides to pass the ball to the SG. The play now looks like this:
The PG now has two options. He can either do a strong side fill or a weak side fill.
Strong side fill
Weak side fill
You should notice the difference immediately. A strong side fill is when the PG moves to the corner on the same side as the ball has been passed to. A weak side fill is a move to opposite corner of the ball.
The same options are available if the PG had passed to the SF on the number 1 pass.
You may have also noticed that we now have the triangle formation. A strong side fill formed a triangle between the SG, PF, and PG on the side of the court the ball was passed to, a weak side fill has formed a triangle on the side opposite the ball between the SF, C, and PG.
How does the PG decide which fill to make? It's based on the moment of truth discussed earlier. The PG makes the first read of the defense at that point and decides whether the triangle should be initiated by the SG or the SF and whether he should do a strong side fill or a weak side fill. The only purpose this serves is to decide where the triangle will be formed and what options will be available for the number 2 pass (discussed later).
This is the most common way to form the triangle, however, sometimes the triangle is formed by dribble entry. Rather than the PG bringing the ball up the court then passing to a wing, a SG, SF, or sometimes PF (think Odom) dribbles the ball to the wing position and the PG immediately fills a corner to initiate the triangle. Alternatively, the PG might stay in the defensive balance position and the triangle might be formed immediately.
After Triangle Formation
Let's look again at what the strong side and weak side fills have created other than a triangle. Look at the  weak side fill [RES ignored duplicate image] first. You'll notice that the SG and PF have half the court to themselves. This can create a good place for a pick and roll if the PF slides up and sets a pick, the SG can pass the ball to the PF and let him work, or they can do any number of combinations of a two man game.
This can also lead to an isolation play for the SG or PF. The PF can slide across the lane and give the SG an isolation ( Picture ) or the SG can slide across the perimeter and give an isolation to the PF ( Picture ).
Remember, that the triangle offense is a read-and-react offense so the offense should not dedicate itself to one particular option, but instead be ready to adapt to what the defense gives them.
Let's look at an example using what we already know.
The clip we'll be looking at is  this one.
The clip begins with the SG with the ball on the wing. Let's diagram the play right now.
This was either the result of a dribble entry or number 1 pass from the PG to the SG. The result is an isolation for the SG with a weak side triangle and the PG at the defensive balance. The defense has made a decision to focus on the SG on his isolation plays so you see the defense's PG hedging toward the SG and the defense's SF hedging toward the lane for help defense on dribble penetration by the SG.
The defense successfully stops the isolation and causes the SG to pick up his dribble. This signals the rest of the offense to help the SG. This is accomplished by the PG moving to the wing position, the SF moving to defensive balance, the C cutting to the strong side post, and the PF moving to the weak side post.
You probably now notice the triangle has been formed between the PG, SG, and C. This was accomplished by what is known as a center opposite. Center opposite is a cut by the C across the lane. In this instance it was a quick cut across the lane but this can also be done by having the PF screen the C's defender to either provide space for a pass or cause a mismatch between the PF and C. You might also notice that the PG is far off the 3pt line. This is to maintain one of the central principles of the triangle offense - spacing.
The SG passes the ball to the PG who then immediately passes to the PF who was free to receive the pass after thecenter opposite. After passing the ball the SG sealed his man which gave him a lane to the basket, the PF does a short bounce pass followed by a screen and the SG makes the basket. Also notice that the PF's slide in the low post gives him great positioning for a rebound.
The next example we'll look at is from this clip running from 6sec to 14sec in the video.
The beginning of the play isn't in the video but likely what happened was the PG dribbled the ball up and after crossing the moment of truth passed the ball to the lag player (the SG), which reversed the play from the left side of the floor (from the offense's perspective) to the right side. This gives the SG the option for the number 1 pass, which he then makes to the SF on the wing.
It's slightly confusing so hopefully these pictures will illustrate what I mean:
Moment of truth crossed, PG swings the ball to the SG, reversing the side of the floor the play will be initiated on
The PF was slow to fill the post and covered pretty well so the SF makes the number 2 pass back to the SG atdefensive balance. This triggers a number of motions. First, the C flashes upward toward the SG for a pinch post option between the SG and C. The PG attempts to make a banana cut to the opposite corner but is guarded pretty well. The SF moves for a rebound cut but instead the PF and SF screen for the PG who curls toward the wing and takes the shot, meanwhile the C after showing a pick for the SG makes a strong rebound cut toward the basket.
Let's stop for a moment and analyze this a bit further. What if the SG had opted for the pinch post? The pinch post would have looked like this.
The PG would have made the banana cut to the opposite corner and the C would have dropped down to the post.
Look familiar? We now have a strong side fill by the PG creating the triangle off of a pinch post. At this point the SF can either move to defensive balance to reverse the triangle, or remain in the weakside wing.
This possession really highlights the players' ability to read and react to everything around them. The PG read the right side of the floor to start the play on, the SF recognized a poor line of deployment (the line of deploymentis a principle where an entry pass to the post should occur at a 45 degree angle between the baseline and the passing direction and the passer reads which side the defender is on to determine which side he should pass to -Picture ), the SG then saw a weak pinch post option, the SF and PF saw a failed banana cut by the PG, and everyone reacted to these correctly to get an open shot for the PG.
So far we've seen a few different ways to form the triangle. We've seen a dribble entry to the wing and we've seen a number 2 pass to the wing. Now let's look at a pass to the post.
The first clip we'll look at is here.
The clip begins with the PG bringing the ball up the court, the C in the lag position, the SG in the wing, the SF in the low post and PF in the high post. Typically we have seen the SG in the lag position but having a versatile roster allows you to have any player fill nearly any position. Remember, everyone is considered an offensive threat in the triangle offense thus versatility is key.
The number 2 pass to the PF keys a couple of movements. The PG settles into defensive balance position, the SG initiates a wing reversal. This means the SG will make a curl from his wing position to the opposite wing position and the C will fill his previous position.
What this has done is free up a lane to the basket for the SG that the PF has an option to pass to.
It also gives an option to pass to the C, and it gives an option to pass to the PG at defensive balance to reverse the play. In this instance the PF passes to the C for an open shot. Remember one of our key principles to the triangle offense, everyone is considered an offensive threat. With that in mind, compare our clip to this one. It's the same play but this time the SF is initiating a wing reversal and the SG is filling his wing position.
Let's see what the play would look like if it had played out completely.
And now we're back to the reset position where the PG can make the number 1 pass to either wing. The triangle can then be reformed by passing to the SG, followed by a strong/weak side fill by the PG
or a center opposite (though in this case the PF would play the role of the center) by cutting the PF across the lane, the C moving into the low post, and the SF cutting to the corner.
Wrinkles to the Triangle
Sometimes the triangle offense can be a little harder to spot, remember that this is an ideal framework so you need to think about the intent of the offense and not what actually happens. For example, let's look at this clip from 4m29sec to 4min36sec.
The play presumably began with a pass from the PG to the SG on the wing and the PG starts a strong side fill.
In the process of the fill, the SG reads and reacts to what the defense has given him and sees an open lane to the basket.
Four defenders collapse on the SG and he finds an open pass to the C for the basket.
Even though the triangle never fully set up, this was still within the framework of the triangle offense. The offense requires its players to take the open opportunities when they present themselves and that was what occurred here.
Incorporation of Plays
Earlier we mentioned dribble entries to the triangle, but a dribble entry is not exclusive to a dribble entry to the wing position. In this clip we see a dribble entry to the corner.
The PG brings the ball up, the C is in the lag position, the PF flashes to the high post, the SF fills the wing, and the SG is in the weak side post. So far do you see any similarities to this set up? It begins very similar to the wing reversal that we saw earlier, except rather than passing to the PF at the high post the SF screens for the PG who then does a dribble entry to the corner. The SF then makes a quick cut to the basket using the PF as a screen and receives the pass for the basket.
This play really demonstrates why the triangle offense is a framework and not a play. You can incorporate plays into the triangle offense while keeping the principles of the offense intact. This play is essentially the same as a 1-4 UCLA cut. Do you see the difference between our clip and this one?
The difference between our clip and that one is our clip used the PG to dribble enter the corner rather than a PG to SG pass to the wing. Both clips utilize the PF for a high screen to the basket.
Triangle as an Out of Bounds Play (Token Timberwolves Clip)
In this clip we see the triangle form as a part of an out of bounds play. The play creates a top of the arc isolation with the triangle formed on the left side of the court. This is a different isolation than what we've seen before with a weak side triangle. Two things should be immediately apparent. First, Beasley is going right, it's too crowded to go left where the triangle is formed. Second, Beasley heads right into the right corner defender to try to free up the corner pass as a second option.
This was intended to serve as only a basic introduction to the triangle offense. Hopefully at the very least it demonstrates the complexity and fluidity of how the offense works. If I can find some more clips to break down I might add them. I'll end this for now and if anyone has questions I can try to answer them when I get a chance. I think I'll do another analysis sometime during the week next week for one of the remaining playoff teams.
Let me know which of the four remaining teams you prefer me to go over. I can't promise the most popular one will be my next pick because it will mostly be influenced by my ability to find/make clips but I can keep it in consideration.