A Visual History of NBA Spacing

We’re living in the Pace and Space era, so spacing is kind of a big deal. So much so that I’d guess nearly everyone who isn’t a coach still undervalues its importance and the role it has played historically in dictating NBA tendencies and strategy. There was a time when the lane looked more like a rugby scrum than a spacious ballroom dance floor, and this post is a visual chronicle of that transformation. Jump in a DeLorean with me as we go back to a rainy November 12, 1955 grainy 1962…

Our first screenshot is from the ’62 Finals. Offensive players have white circles under them to denote their location, defensive players blue ones, and the ball handler is white surrounded by blue.

This was what an “open lane” looked like for much of the 60s. There are four defenders on the edge of the modern (16-foot wide) key ready to help on that ball-handler if he attacks. Notice, also, that if he drives left toward the baseline, something convoluted happens: He will try to use his teammates as screeners like they are offensive linemen in football, but help defense was easy because everything so tightly packed.

Guard play in the ’60s was also characterized by a palm-down (pronated) dribble. The effect of this cannot be overstated — guards simply were not allowed to dribble in any modern capacity, which made penetration into this congested traffic difficult. Bob Cousy didn’t dribble like this for fun, the rules demanded it.

The next image is quite grainy, but it was so typical of the times that it must be included. The ball is on the far wing, at most, nine feet from the man posting up (Wilt Chamberlain). There are eight players in the modern key!

It was common at the time for certain post plays to start with this much traffic, and it led to a practice I call the “free double-team.” Modern double-teams usually pay a price by leaving a player open. The free double-team is a costless defensive trap, in which the help-defender’s own man is still so close that he can effectively guard two players at once. Thus, despite being doubled, the ball-handler can’t create a shot for an open teammate.

In the ensuing years, teams and coaches were certainly aware of these issues. The Princeton offense — which now comes in many flavors — had a large emphasis on balanced spacing and opening the lane. Still, it was a slow crawl to where we are today. The inability to break down defenders off the dribble didn’t leave coaches dreaming of clear-outs.

If we jump ahead to the 1970 Finals, you’ll notice there’s a little more breathing room.

The Lakers have pulled two players (somewhat) high and wide on the weak side, and there’s now sufficient space between the entry passer (Elgin Baylor) and Wilt in the post. However, any drive from Baylor will encounter two fundamental problems. First, there are three defenders in the lane. Second, it will be hard to punish any help defenders. The best option is likely a kick-out for a long two, but the two spot-up players are within feet of each other and can be covered by one man!

From the same game, L.A. runs a more modern type of isolation for Jerry West, who liked to back his defender down from the high post. The screen capture is from the moment New York sends a double at West.

It’s not “free” in that L.A. is spread out enough for him to swing it to an open teammate at the top of the key. Notice how pinched down the weak side players are, allowing the Knicks to form a wall in the lane, deterring penetration. It’s an improvement from the early 60s, but it’s an “economy to economy-plus” improvement. This isn’t business class space.

There isn’t much footage from the 60s, but from the publicly available film, it wasn’t until the 1970 season that the NBA started easing up on palming. Players still dribbled with mostly pronated wrists, but the contact point of the ball could be held a little longer. (I credit the ABA’s free style of play for slowly relaxing the enforcement of these rules.) More secure ball-handling made it easier to penetrate into space…if there was any.

By the early 70s, offenses were starting to expand the court. Here’s our first example of some business class roominess (from 1974):

That screenshot was taken as the entry pass reached Kareem Abdul-Jabbar at the elbow. This kind of space was a game-changer; there would now be a hefty price for doubling Kareem with either the baseline defender or the diagonal defender near the foul line. And of course, Kareem himself has a lot of room to operate in isolation, and you don’t want to play Kareem one on one.

The ’70s were a mixture of viable spacing like this and the crammed confines of the ’60s. However, like a frog in boiling water, the dribbling rules continued to slowly relax . You can see some wrist rotation during this open court dribble from David Thompson in 1977, and then a full 90-degree wrist when he hesitates on the following play. By the early ’80s, players were fully turning their wrists over from the side (or underneath) the ball. Isiah Thomas was perhaps the most notable perpetrator, and the technique can be seen on his left-to-right crossover here.

In 1980, the NBA introduced the 3-point line, but it took a few years for spacing to expand to the arc. Here’s a typical Laker set from 1983, in which Magic Johnson’s entry to Kareem was four feet inside the stripe and the entire Laker offense is indifferent to the 3-point line. (Yes, Magic’s defender is daring him to take that shot.)

Notice that there are still five Denver defenders in the lane. However, offenses in the ’70s and ’80s distributed players evenly among the strong and weak side, particularly after the introduction of illegal defense in 1982, which permitted offenses to pull shot-blockers out of the lane. More on this in a second.

By the mid ’80s, the combination of improved spacing and efficacious dribbling made penetration and isolation more of a threat. This coincided with a steady improvement in offensive efficiency — in just over a decade, league-wide ratings exploded from the mid 90s to 107 points per 100 in 1982, within two points of the all-time peak.

Let’s hop forward to 1990 and snap an image of Chicago’s famed triangle offense, which emphasized spacing and balance:

Right away it should be clear that this is business class roominess. Michael Jordan is initiating the offense here, and Chicago’s spacing allows for, at the least, a drive-and-kick by Jordan. More importantly — at least for Shaquille O’Neal 10 years later — the post player’s life is easier with three teammates out beyond the arc and the opposite side big near the high post. This kind of spacing means the defense has to cover longer distances to rotate and makes interior passing more realistic.

Compare this to, say, Hakeem Olajuwon’s Rockets, who liked to use “3 out” and “4 out” sets, pinning shooters to the 3-point line in order to punish an Olajuwon double. This next caption (from 1994) is snapped after the ball has been kicked out of the post.

Utah still has an amoeba-like wall in the lane, but the threat of the outside shot forces the defense to close out on the shooters, which can re-open a driving lane. This was very much a read-and-react game, in which the spacing allowed teams to move the ball to the best shot, and defenses scrambled to stop that shot. Here’s an example of a “4 out” set from the same year:

Now there’s only one Utah defender in the paint and some decent real estate to work with. At the same time, many teams were starting to abuse the illegal defense rules by pulling entire defenses out of the lane.

That group of Spurs bunched together on the right side of the screen cannot legally drop below the foul line because Utah has stationed the rest of its team above the arc. Some version of this play was run constantly in the ’90s, particularly by teams with good isolation players. As you can see, it frees up a ton of space to attack; David Robinson is on a basketball island defending Karl Malone. If something breaks down, defenders from above the foul line, like Tim Duncan, will have to race down to protect the rim.

At the same time, the seeds of the modern pick-and-roll dominant game were being sewn. NBA teams have been pick-and-rolling forever, but the 3-point shot and spacing have supercharged its power. Here’s a famous Malone-Stockton sideline pick-and-roll. Notice how much space is created by stationing two players at the 3-point arc.

This play is so difficult to contain that it forces the weak side defender to completely leave his man in the lower right corner. Just the setup can create an open shot with a skip pass.

Of course, by this point in time, you could completely supinate your hand when dribbling, pause, and continue dribbling some more. As a result, quick guards were nearly impossible to contain when given space to attack. Before 1995, hand-checking was permitted above the free throw line, which could somewhat mitigate this effect, but the flood gates opened in the mid-’90s. The defensive counter to eliminating true hand-checking was to bump and arm bar players when they moved off the ball, which was then eliminated in 2005’s rule change emphasizing “freedom of movement.” All of this laid the foundation for today’s game.

Let’s jump a few more years to an isolation-heavy offense, the 2006 Lakers, and a Kobe Bryant drive:

Look at all that beautiful open court to attack! If help comes from anywhere, Kobe should be able to find an open shooter or cutter. This was the same kind of read-and-react game from the ’90s, only with better spacing principles (increased 3-point shooting) and no illegal defense (abolished in 2002 for defensive 3 seconds). Some teams were even initiating offenses with all five guys around the arc.

This is really difficult to guard. The threat of the shooters, and the space needed to help off of them and then recover strains defenses, who must pick-a-poison whenever the player initiating the pick-and-roll is an offensive weapon (like Steve Nash). The NBA moved toward this approach during the last decade, as 3-point shooting became more prevalent and stretch bigs helped open up the court. This has driven up individual scoring rates, led to a rise in creation and helped the league set an efficiency record in 2017.

Finally, you’ve earned it. Let’s enjoy the first-class experience:

Ladies and gentlemen, that is a high pick-and-roll 10 feet beyond the 3-point line, with three shooters pinning the defense to the arc. This is the game today — lots of space, threats everywhere and minimal congestion on cuts. That wide-open shaded area in the above screenshot is at least 350 square feet, the size of a New York City apartment.

Or, in the old days, the home of most of the defenders on the court.

From the Vault: Are Role Players Worse on the Road

This post was originally published on June 3, 2012. 

On the ESPN pregame show before Game 4 of the Eastern Conference Finals between Boston and Miami, there was a long discussion about why peripheral players tend to struggle more on the road than at home. Which, of course, begs the question…do peripheral players really struggle more on the road than at home?

If we break down player importance by minutes played, we can stratify everyone in the NBA into six categories, ranging from guys who play under 15 minutes per game to those who play more than 35. This is what the results look like for free throw shooting:

Free Throw% Away Home Diff Away % of Home
Players Over 35 mpg .763 .757 -.006 100.8%
30-35 .796 .795 -.001 100.1%
25-30 .774 .768 -.005 100.7%
20-25 .712 .722 .011 98.5%
15-20 .707 .689 -.018 102.6%
Under 15 .677 .675 -.002 100.3%

This confirms another myth-buster we learned at the Sloan MIT Sports Conference this year: teams shoot free throws better on the road, not at home. Players over 35 minutes per game see a small improvement on the road, with home-cooking only reserved for players in the 20 to 25 minute bracket. Those players see a 1.1% decrease in free throw shooting on the road.

Obviously, free throw shooting isn’t a category that tells us much. Instead, let’s look at overall box score statistics that ballpark play based on the basic box stats. First, Game Score (similar to PER) and then Expected Value run only on the box score stats. Finally, points per game and True Shooting% are included.

Game Score Away Home Diff Away % of Home
Players Over 35 mpg 14.6 15.7 1.1 93.2%
30-35 11.1 12.0 0.9 92.5%
25-30 7.7 8.7 0.9 89.4%
20-25 5.9 6.1 0.2 96.8%
15-20 4.0 4.0 0.0 99.8%
Under 15 2.2 2.4 0.2 90.9%
Box EV Away Home Diff Away % of Home
Players Over 35 mpg 4.5 5.4 0.8 84.3%
30-35 3.8 4.4 0.6 87.4%
25-30 2.9 3.4 0.5 84.0%
20-25 2.3 2.5 0.2 92.6%
15-20 1.5 1.5 -0.3 102.2%
Under 15 0.6 0.7 0.1 85.9%
Points Per Game Away Home Diff Away % of Home
Players Over 35 mpg 18.95 19.62 0.7 96.6%
30-35 14.75 15.36 0.6 96.0%
25-30 10.79 11.17 0.4 96.6%
20-25 7.81 7.81 0.0 100.0%
15-20 5.43 5.31 -0.1 102.2%
Under 15 3.18 3.33 0.2 95.5%
True Shooting% Away Home Diff Away % of Home
Players Over 35 mpg .535 .556 .021 96.2%
30-35 .534 .554 .020 96.4%
25-30 .522 .534 .013 97.6%
20-25 .520 .519 -.001 100.2%
15-20 .506 .506 .000 100.0%
Under 15 .471 .485 .013 97.2%

Based on these measurements, lower minute players are actually more consistent on the road than they are away from home. Consider:

  • 25-30 minute players decrease the most on the road by Game Score and Box-based EV
  • 25-30 minute player see no decline in points per game and TS%
  • Under 15 minute players see a Road decline comparable to high minute players in points and efficiency

Otherwise, the players with the biggest drop-off in road performance are the high-minute players! Whether it’s composite box metrics or scoring and shooting, the biggest difference between road and home is typically seen in the key players. In the composite metrics especially, the high-minute players see a significantly larger decline on the road than the low-minute players do.

Keep in mind this is not a definitive study, but a broad examination. We could change the criteria to examine “only All-Stars” or “only All-Stars in the playoffs,” and it’s possible the results look different. But it’s important to note, that in general, it is not the role players who decline more on the road, but the stars.

Half-Court Math: Hack-a-Whoever, Isolation and Long 2’s

In my upcoming book, Thinking Basketball, I allude to certain instances where “low efficiency” isolation offense provides value for teams. Most of us compare a player’s efficiency to the overall team or league average, but that’s not quite how the math works, because the average half-court possession is worth less than the average overall possession.

In 2016, the typical NBA possession was worth about 1.06 points. That’s a sample that includes half-court possessions against a set defense, but also scoring attempts from:

  • transition
  • loose-ball fouls
  • intentional fouls
  • technical fouls

Transition is by far the largest subset of that group, accounting for 15% of possessions for teams, per Synergy Sports play-tracking estimations. Not surprisingly, transition chances, when the defense is not set, are worth far more than half-court chances. As are all of the free-throw shooting possessions that occur outside of the half-court offense.

Strip away those premium opportunities from transition and miscellaneous free throws and the 2016 league averaged 95 points per 100 half-court possessions. (All teams were between 7 and 14 points worse in the half-court than their overall efficiency.) Golden State, the best half-court offense in the league this year, tallied an offensive rating around 105, far off its overall number of 115 that analysts are used to seeing.

Transition vs Half Court Efficiency

This has major implications for the math behind “Hack-A-Whoever.” If the defense is set, then, all things being equal, fouling someone who shoots over 50% from the free throw line is doing them a favor. One might think that a 53% free throw shooter (1.06 points per attempt) at the line is below league average on offense because of the overall offensive efficiency. But it’s actually well above league average against a set, half-court defense. (Other factors, like offensive rebounding and allowing the free-throw shooters team to set-up on defense complicate the equation.)

Said another way — fouling a 53% free throw shooter is similar to giving up a 53% 2-point attempt…which is woeful half-court defense.

There could be other viable reasons to “Hack-A-Whoever,” such as breaking up an opponent’s rhythm or psychologically disrupting the fouled player. (These would be good strategic reasons to keep the rule, in my opinion.) But assuming he was a 50-60% foul shooter, coaches would still be making a short-term tradeoff, exchanging an inefficient defensive possession for other strategic gains.

This also has ramifications for isolation scorers and long 2-point shots. Isolation matchups that create around a point per possession in the half court — or “only” 50% true shooting — are indeed excellent possessions. If defenses don’t react accordingly, they will be burned by such efficiency in the half-court. As an example, San Antonio registered about 103 points per 100 half-court possessions this year, and combined it with a below-average transition attack to still finish with an offensive rating of 110, fourth-best in the league.

The same goes for the dreaded mid-range or long 2-pointer — giving these shots to excellent shooters from that range (around 50% conversion) is a subpar defensive strategy. And even a 35% 3-point shooter (1.05 points per shot) yields elite half-court offense.

So, when we talk about the Expected Value of certain strategies, mixing transition possessions together with half-court ones will warp the numbers. Sometimes, seemingly below-average efficiency is actually quite good.