Ball Movement and People Movement

Apr 1, 2015; Orlando, FL, USA; San Antonio Spurs guard Tony Parker (9) drives to the basket against the Orlando Magic during the second half at Amway Center. San Antonio Spurs defeated the Orlando Magic 103-91. Mandatory Credit: Kim Klement-USA TODAY Sports

Two of the fundamental components of basketball at any level are ball movement and moving without the basketball. Proper use of both can help create open shots by forcing the defense to work harder to stay with their man and make reads on and off of the ball. In the NBA, there are teams that have carved out a niche as super high-motion teams that cover large distances per game. Others teams have become uniquely high-volume passers, nearly ridding themselves of isolation possessions or possessions where the ball sticks to one player. A few teams, have mastered both.

People Movement

What do the top three point guards in distance traveled per 48 minutes have in common? They all play for the San Antonio Spurs.

This isn’t a coincidence or something that happened because they got three of the fastest, or most hyperactive point guards in the league. It is a result of their offense. San Antonio is unique in the NBA in how far all of their players run per 48 minutes, especially their point guards and wing players. As a team they run 89,650 feet per 48 minutes, nearly 2,000 feet farther than the 76ers who rank second in that category, and over 4,500 feet more than league average. For at least the second straight year they have had a significant lead over the rest of the league in that category[1. SportVU player tracking data only goes back to 2013-14.].

Note: The Y-axis begins at 82,000 feet. The gap between 1st and 30th in distance per 48 minutes is about 6,000 feet.

What makes this even more significant is the fact that they cover so much ground despite playing at the 18th fastest pace in the league. Presumably, teams that play fewer possessions per game won’t run as far as teams that play more possessions since the easiest way to add mileage to the pedometer is to get up and down the court. There is, in fact, a slight correlation between team pace and team distance run per 48 minutes and both the Warriors and 76ers are among the league leaders in both categories. However, the Spurs are practically league average in the number of times they run up and down the court, making their total distance per 48 minutes even more of an anomaly.

The trendline shows the expected distance a team would run based on their pace. Teams above the trendline run more than expected. Teams below the trendline run less than expected.

The Spurs accomplish this by having the league’s best Half Court Pace (HCP), a metric I introduced last fall that attempts to measure how far a team runs on each possession. The metric is fairly noisy[2. The issue is that I am most interested in measuring how much a team runs on offense however in this case, 1 possession equals one offensive and defensive possession.  There is also some noise from the number and quality of fast breaks. A team can steal an inbound pass and lay it in the basket in a matter of seconds and with very little player movement. Plays like that will skew HCP. However, as a rough measure for team tendencies and placed alongside things like individual player distance per 48 minutes, I think it is still a worthwhile metric when used appropriately]. as a measure for offensive movement for reasons that I mention in my previous articles, but when placed alongside data about individual distance per 48 you get an idea for which teams move the most in their half court offense.

Half Court pace is calculated by subtracting expected distance per 48 minutes from actual distance per 48 minutes. Positive values indicate that a team runs

more

than average while a team with a negative score would run

less

than average.

It’s obvious just from watching the Spurs play that player movement is a large part of their offensive identity. In addition to having the three top-ranked point guards in distance per 48 minutes, they also have two of the top 10 shooting guards in Danny Green (3rd) and Marco Belinelli (7th), the 11th ranked small forward in Kawhi Leonard, and the 8th and 13th ranked centers in Tiago Splitter and Aron Baynes[3. Minimum of 15 mpg, 10 gp.]. The power forward position is the only spot where the Spurs are average in distance per 48 minutes. Tim Duncan is ranked 20th among power forwards and Boris Diaw is ranked 70th.

Ranking distance run per 48 minutes by position.  Minimum 15 MPG, 10 GP

Anybody that has played pickup basketball knows why player movement is difficult to guard.  Nobody wants to guard the speedy guy on the court that never stops running around on offense. It requires a lot of focus and effort to constantly calculate things like when to provide help defense or when to switch on screens while guarding a guy that never stands still on the weak side. When all five guys on the court are in constant motion it becomes even more difficult to calibrate complex rotations like when to ice or switch a screen or who not to leave open in the corner.

Ball Movement

Player movement isn’t the only way to put pressure on a defense.  When Alvin Gentry joined the Warriors’ coaching staff last summer, he described his offensive philosophy as a focus on “ball movement and people movement.” According to Half Court Pace, the Warriors rank 3rd in “people movement,” but their ball movement is equally as impressive.

This season, the Warriors rank 7th in the league with 313.2 passes per 48 minutes, nearly 70 more passes per 48 minutes than in 2013-14. Their Potential Assist Percentage[4. The ratio of assist opportunities to field goal attempts. The top 5 teams in PA% this season: Hawks, Warriors, Celtics, Spurs and Clippers.] has increased from a ranking of 22nd in the league last season, to second in the league this season, meaning not only are they passing more, but their passes are leading to more assisted opportunities. In short, their passes are getting open looks.

In his blog a few days ago, Michael Beuoy introduced a way to measure the average length of each team’s offensive possession. This is a more accurate way of estimating a team’s pace since it takes out the defensive variable. The Warriors, who lead the league in pace by over a full possession per game, are actually even more of an outlier when you look at their average length of possession. At 13.4 seconds per possession, the Warriors are a full second quicker than the second fastest team, the Houston Rockets.

Given the total passes per 48 minutes, the total possessions per 48 minutes, and the average length of possession, we can calculate the average number of passes per possession and the average number of seconds between each pass. This gives us a pretty clear idea of which teams are sharing the ball most frequently and as you might assume, the Warriors, Hawks and Spurs are among the league’s most frequent passers.

Although the Warriors shoot the quickest on average, they still pass the ball quicker than most teams.

However, while teams like the Spurs and Warriors have a clear emphasis on getting their players and the basketball moving, there isn’t a league-wide positive correlation between more movement and higher offensive rating. Three of the top four teams in ORtg, the Cavaliers, Raptors and Clippers, are also three of the bottom four in Half Court Pace. In fact, many of the top teams in ORtg have negative Half Court Pace scores. Those same teams also score fairly low in seconds between passes. On the flip side, the Knicks and 76ers are two of the worst offensive teams in the league yet rank very high in both metrics.

The metric doesn’t appear to reveal substantive advantages as much as it measures stylistic differences. The Hawks, Warriors and Spurs run players off of screens, whip the ball around the perimeter and drive and kick to get open looks. Teams like the Clippers and Cavaliers are much different in their approach. Whereas the Spurs rely on everybody on the court to contribute to creating open shots, superstar players like Lebron James and Chris Paul create a majority of their team’s open shots by virtue of their talent and court vision.

This stylistic difference is demonstrated in the two videos below.  In the first clip, notice how effective Lebron and the Cavs are at creating open shots by sticking stagnant shooters around the perimeter and running high pick and roll. Lebron demands a double team out of the pick-and-roll since he is one of the greatest finishers at the rim that the league has ever seen. Even without moving, players like J.R. Smith and Kyrie Irving are able to space the court enough to create a sort of 3-on-3 situation for Lebron and the two other players inside the 3-point circle. The result is an offensive set that can get any number of efficient FGA’s. In the video below, the Cavs get shots at the rim, shots in the corner and wide open mid range jumpers.

The set works so well because of the talent on the court. If you substitute Lebron James for Rudy Gay, that set immediately become less effective. This is a large part of why “Jim’s and Joe’s trump X’s and O’s,” but that isn’t to say that X’s and O’s aren’t important. Teams with marginally less talented Jim’s and Joe’s just have to work harder (or at least they have to work differently) to create equally as efficient FGAs. That’s where ball movement and people movement comes in. In this clip, the Spurs run Belinelli, Parker, and Leonard off of screens before the second pass is made. From there, several players look to attack the basket quickly and kick if/when the defense collapses. The Spurs make a total of six passes and the defense is forced to scramble several times before giving up an open shot at the rim.

The two different plays represent different levels of half court pace and time between passes. While both teams run stagnant sets and high motion sets on occasion, the Cavaliers rely much more heavily on sets like the first one. None of this is to say that one method is objectively better than the other. The Heat won two championships in 2012 and 2013 behind the stagnant, spread offense led by Lebron James. The Spurs won a championship in 2014 behind their high motion and passing offense that relied on all five players on the court. In both cases, the team requires a certain type of talent.

Team’s that don’t play to their strength end up with results like the Denver Nuggets, a team that for most of the season was among the most stagnant and least frequent passing teams in the league despite having a fairly balanced roster and lacking a single superstar talent. On the other end of the spectrum, teams like the 76ers are attempting to create an offensive identity that requires a lot of cutting and passing yet they lack the overall talent to execute it the way the Spurs do.

Lastly, the Warriors present a fairly curious case. They have superstar talent in Steph Curry yet they also have a roster full of talented role players that they can rely on to make smart, quick reads with the basketball. They are something of a combination of the two contrasting styles. Curry ranks 29th in time of possession per game, despite playing more minutes per game than 20 of the 29 people ahead of him. They are a rare case of a team with a transcendent player that still leans on the talent of the roster around him to create efficient FGAs.

All teams took notice when the Spurs won the finals with the model of ball movement and people movement. Perhaps the Warriors are taking it to the next level.