Second Chances and the Rebounding Specialist

A tried-but-true strategy in pick-up (and grade school) basketball is the “dump-and-chase” offense. This offense takes as many jumpers as possible, regardless of capability, fully knowing that the team can either out-hustle their opponent for rebounds; or they have a behemoth of a rebounder on their team. As players become older, or more technically sound on defense, the successful ability to employ this strategy becomes not as possible; however the strategy still exists in a different form: the rebounding specialist. The rebounding specialist is a player who’s primary purpose is to rebound. Commonly, rebounding specialists can also be rim protectors or they can be rim runners. Some lesser known dirty jobs for some of these specialists are space creators / lane clearers / screen setters.

When we discuss these roles, we usually can identify clear examples. For instance, when we think of rim protectors, we think of guys who cover the lane quickly and can not only rebound, but gather blocks like Dikembe Mutombo or Roy Hibbert. When we think of rim runners, we think of the guys who crash the boards hard from outside the paint like Clint Capela or Amar’e Stoudemire. When we think of space creators, we identify the guys who box out well and may not get as many rebounds like  Robin Lopez.

Regardless of their sub-specialties, the end goal of their specialty is simple: create space and get boards. Sure, some of these players score as well; the more capable a scorer, the better… but as we will soon find out, this is not theses players specialties. What these players ultimately become are our forgiving teammates: the ones who yield second chances.

Second Chances

A chance is a a sub-possession quantity that measures the possibility of scoring a basket. Anytime that sub-possession terminates, either the possession ends or another new chance emerges. Common ways to terminate a chance is to attempt a field goal, turn the ball over, or termination of a period. This is not to be confused with NBA Stat’s awkward definition of Second Chance Points:

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Definition of second chance points via: https://stats.nba.com/help/glossary/

As a personal side note: playing at all levels except professional and working on or with coaching staffs at all levels including professional, this has never been the indication of what second chance points means. Opposed to being a “free-throw” definition, second chance points has been commonly defined as “any points scored after an offensive rebound.” We are going to roll with this traditional definition.

Second chances are just that: An offense failed to score on their first field goal attempt and an offensive player has bailed the offense out by securing the rebound. This breathes new life into the possession and gives the team an extra chance at scoring! Dump-and-chase is still alive.

By having a rebounding specialist on the team, an offense can enjoy a couple benefits such as shooting perimeter shots at will and forcing the defense to find the lurking rebounder. There are some drawbacks to having a rebounding specialist on the court such as poor free throw shooting and poor perimeter shooting, but dependent on the team structure, these drawbacks may be overlooked.

So how much of an impact do these rebounding specialists have on the game?

Impact on a Possession

A rebounding specialist is a forgiving teammate as they are erasing the mistakes of a teammate with their rebound. Often times, it may be their own mistake. To understand their impact, we become interested in what these teammates do with the ball after they have secured the rebound.

Commonly, teams strive to hit the 1.10 points per possession mark. In a 100 possession game, this equates to 110 points scored; which typically ensures a win. Using this value as a benchmark, we would then be interested not only on the offensive rebounding potential of a player, but we are also interested in their points per offensive rebound. Think of this as a lower bound on their points per possession mark; as multiple offensive rebounds may occur on a possession.

So who are the top offensive rebounders in the league?

We can do the naive thing and sort players by their offensive rebounding percentage, but we’d end up with Jack Cooley being the top offensive rebounder in the league. We can do the other naive thing and impose an arbitrary cut-off that makes little to no sense, such as “minimum 1000 minutes played.” Then Golden State’s starting Center, Zaza Pachulia, is eliminated. Yes, he started 57 games at center in the 2017-18 NBA season.

Instead, we focus on the count of offensive rebounds and adjust as necessary with offensive rebounding percentage. A common tactic is to perform the cross-product value: OREB*OREB / (OREB + OppDREB). We can use other denominators such as “total rebounds” which encapsulates team rebounds as well. If we play off this list, we obtain the following ranking:

 

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Top 35 Offensive Rebounders through the Cross-Product Statistic

 

We immediately see the usual suspects at the top of this list: Andre Drummond, Steven Adams, and DeAndre Jordan. Some are lower on the list than expected due to lower offensive rebound counts such as Hassan Whiteside (missed 28 games) and Tyson Chandler (missed 36 games). Others are lower because their team took many missed FG’s such as Anthony Davis (13th in league in OREB but only 7.7% OREB%) and Taj Gibson (12th in league in OREB but only 8.1% OREB%).

The above list are your prime candidates for who the rebounding specialists are. From here, we become more interested on their impact on possessions. IE: Who’s more dangerous when an offensive rebound occurs… Domantas Sabonis or Thaddeus Young? Or relatable: Do we game plan for Steven Adams the same as we would for Andre Drummond?

Partitioning Play-By-Play

We are able to partition play-by-play and start understanding what happens when an offensive rebound is obtained. For instance, we can initialize a rebounder dictionary and keep track of secondary chances:

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And then from there, it’s a simple iterrows walk through the game file:

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Simple iterrows walk. First find the second chance, then iterate through possession ending situations. Starting with turnovers, of course.

From this set-up, we identify how many points are scored on second chances. During the course of processing, however, we did find a handful of errors in the NBA play-by-play logs; most concerning time_elapsed and sequence_number. Despite spending several hours hunting these items down, there are a couple persistent ones (and partially a reason to be cautious of play-by-play driven site statistics such as Cleaning the Glass).

Top Points Scorers

To identify the top points scorers, instead of looking at the number of second chance points scored by a player, we credit the rebounder with the points scored. The purpose for this is to identify the impact of the rebounder on the game. Using this philosophy, we obtain the following Top-54 list:

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This is Top-54 by Player-Team. Blake Griffin has two entries in here.

As you can see, these players are sorted as Player / Team. This means that certain players are split up if they played on multiple teams; such as Blake Griffin. In the example of Griffin, he would not fall within the Top-54 players: he contributed to 74 second chance points on 74 offensive rebounds.

Here we see the top three rebounders atop this list as well. However, we see Enes Kanter slide down in favor of Karl-Anthony Towns; as Towns holds an exceptionally impressive 1.37 points per offensive rebound. Differently, Steven Adams leads to less than a point per offensive rebound; identifying that while the Thunder possession is elongated, it’s not necessarily dire straights for the defense. We will take a deeper look at this shortly.

We note that Clint Capela, in line with Houston’s perimeter philosophy, generates lots of three-point attempts (67 out of 242 rebounds); a number only rivaled by Steven Adams as Adams has 11 less (56) despite requiring 142 more offensive rebounds to get there (384).

Another interesting note is that Ben Simmons is the top rebounding guard leading all point guards with contributing to 172 points over 145 offensive rebounds. Russell Westbrook comes in right behind Simmons with 171 points over 151 offensive boards.

The rebounders that improve chances of scoring dramatically? That’s Brook Lopez (1.39), Karl-Anthony Towns (1.37), Nikola Jokic (1.33), Giannis Antetokounmpo (1.32), DeMarcus Cousins (1.32), Pascal Siakam (1.36), Anthony Davis (1.26), Nikola Vucevic (1.26), Ryan Anderson (1.26), and Andrew Wiggins (1.26). The eleventh spot is tied among several players at 1.25 points per OREB: Joel Embiid, Larry Nance Jr., and LeBron James.

Let’s compare some of these players.

1. Andre Drummond – Detroit Pistons

Andre Drummond, despite only 1.03 points per offensive rebound, is considered one of the best offensive rebounders in the game. When coaches game-plan for Detroit, a common theme is to reduce the number of second chance points. And it’s no wonder: Andre Drummond leads the league in generating second chance points. But where do those points come from?

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Distribution of Andre Drummond’s Second Chances

We find that 379 of Drummond’s 414 points generated are scored by himself. A whopping 73% of his offensive rebounds turns into put-backs; of which he is only a 58% shooter. If he gets to the line, he rests at a 58% clip; making it favorable to foul the big man.

However, one item is clear: Detroit’s three point shooting is nonexistent when Drummond rebounds the ball. Detroit managed to go 2-22 (11%) from beyond the arc in such situations. Similarly, the Pistons struggled from the two-point range on Drummond rebounds, shooting below fifty percent at 13-31 (42%).

 

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Distribution of 2017-18 Second Chance FGA courtesy of Andre Drummond.

 

2. DeAndre Jordan – LA Clippers

DeAndre Jordan’s name frequently comes up in tandem with Drummonds thanks to their similar style of play: ferocious put-bank dunks, deterrence to shooters in the lane (on defense), and sub-optimal free throw shooting capability. Jordan lands second on the list for second chance points scored with 364 points, a whopping 50 points less than Drummond; but at a higher rate per offensive rebound at 1.11 points.

Whether it is due to the quality of shooting or how the offense responds to offensive rebounds, the Clippers were far better from the perimeter when Jordan secured offensive boards, coming in at 16-for-33 (48%).

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Distribution of Second Chances from DeAndre Jordan.

 

Here, we find that Jordan only puts-back 62% of his offensive rebounds for a 117-205 (57%) rate. This identifies Jordan as being more efficient with his putbacks when compared to Drummond; as well as improving the opportunities for others to score around him in second chance situations.

Another marked improvement is that Tobias Harris, Austin Rivers, and Wesley Johnson combined to go 11-for-16 from three when Jordan gains offensive rebounds. Despite being small sample sizes, it’s an interesting takeaway that Harris, who split time with both Drummond and Jordan, would go 0-3 in one situation and 3-for-4 in the latter. This doesn’t signify that Jordan is a better passer than Drummond;  but it lends to investigate what are the differences in these situations as commonly 1-2 baskets are the difference between a win and a loss.

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Distribution of 2017-18 Second Chance FGA courtesy of DeAndre Jordan. Purple is used for misses to deconflict with the red paint of the court.

3. Steven Adams – Oklahoma City Thunder

Steven Adams, the third of the big three in second chances, is quite a different player. He’s not much of a dunker; nor is he an intimidating force as a defender (IE: not the first name that pops into your head as a big time blocker). Most importantly, he is the weakest of the three players when it comes to generating points per offensive rebound: 0.93.

Of his 384 offensive boards, only 213 went right back up. This lowly rate of 55% indicates that he is highly likely to kick the ball back out to Westbrook, Carmelo Anthony, or Paul George. That said, 83 of Adams’ 358 points came from those three as Westbrook cashed in on 40 points, Anthony for 22 points, and George for 21 points.

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Distribution of Oklahoma City’s Second Chances from Steven Adams.

An interesting result that pops up from Adams’ distribution of second chances is that Carmelo Anthony is an abysmal 2-for-17 from beyond the three point line. Similarly, Paul George is 2-for-10 from within the arc. This combined 4-for-27 absolutely demolishes Adams’ points per offensive rebound production; aside from mentioning Adams’ spotty free throw shooting capability at 18-for-45 (40%) and the 40 turnovers.

What is gleaned at a high-level from here is that the Thunder are become chaotic after second chance points generated by Steven Adams.

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Distribution of 2017-18 Second Chance FGA courtesy of Steven Adams.

There are some wonky results that pop up under Steven Adams’ teammates. This is simply an issue with time-outs, synchronization of NBA’s play-by-play sequencing, and time elapsed. But there are few and far between and we can ignore the random Cousins, Holiday, and Teague results.

4. Karl-Anthony Towns – Minnesota Timberwolves

With a new contract in hand, we come to Karl-Anthony Towns; the power forward for the Minnesota Timberwolves. Being the best scorer at the top of this list, Towns also establishes his dominance as an offensive rebounding juggernaut by providing 330 points of second-chance offense for his team.

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Distribution of Minnesota’s Second Chances from Karl-Anthony Towns.

Of his 241 offensive rebounds, Towns put back only 57% of his rebounds, giving a significant chance for redistribution of the ball. It shows in his teammates’ production too: Taj Gibson benefited for 20 points, Jamal Crawford cashed in for 18 points, Andrew Wiggins picked up 16 second chance points, and Jimmy Butler got 13 extra points. The distribution means that the Timberwolves could strike from any position; unlike the Thunder’s Big Three Only attack with Adams.

On top of these point totals, his teammates scored. The aforementioned four players shot 19-for-29 for two and 6-for-12 from three. And don’t count on fouling Minnesota: they shot 57-for-70 (81%) from the line. Basically, this means Towns must be kept off the glass at all costs. And if he manages to get an offensive board, good luck.

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Distribution of 2017-18 Second Chance FGA courtesy of Karl-Anthony Towns.

In true Minnesota fashion, they attacked from the right hand side of the basket and attempted many mid-range field goals. What this indicates is that either Towns scored immediately, or they ground-out a new offensive chance as if it were a new possession. Of the four top second chance scorers, Minnesota showed the most poise as they re-ignited their offense in hopes of wearing out a defense and getting the look they actually wanted.

And to drive this home, the most impressive stat of them all: 12 total turnovers.

16. Giannis Antetokounmpo – Milwaukee Bucks

We take a jump from many more centers and power forwards and land at one of our first premier perimeter / inside-out/ ball-handling players on the Top 54 list: Giannis Antetokounmpo of Milwaukee. Antetokounmpo jumps high on this list due to his propensity to get the team to score, as he checks in at 4th on the list of points per offensive rebound.

Antetokounmpo is effectively the agile and dexterous version of DeAndre Jordan when it comes to second chance points. Despite playing further away from the basket, and hence having less opportunity to secure offensive rebounds, 158 to Jordan’s 329, Antetokounmpo puts back 64% of his rebounds for a solid 74% rate: 74-for-101. With an effective field-goal percentage of .718, Antetokounmpo is one of the most efficient scorers in second chance points generated by themselves.

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Distribution of Giannis Antetokounmpo’s Second Chances

Similar to Minnesota, Milwaukee’s performance is fairly efficient on second chances generated by Antetokounmpo, but the quantity is lacking. Only Eric Bledsoe scored in double digits (15 points on 6-for-10 shooting) while Khris Middleton (3-for-7) kept a very pedestrian production level.

Despite this, Milwaukee kept turnovers low: 8 total… a slightly higher rate than Minnesota on Towns’ second chances. An astonishing take-away is that no other Bucks players picked up free throws when Antetokounmpo secured second chances. Compare this to the 15 free throws picked up by Middleton (6-for-7) and Antetokounmpo (4-for-8) when John Henson grabbed 148 offensive rebounds.

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Distribution of 2017-18 Second Chance FGA courtesy of Giannis Antetokounmpo.

 

26. Russell Westbrook – Oklahoma City Thunder

We skip over the number one rebounding point guard (Ben Simmons) in favor of the triple-double machine in Russell Westbrook. Westbrook managed to secure 152 offensive rebounds this past season and turned them into 171 points, which is above the 1.10 points per possession line. How he did it, however, is quite interesting.

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Distribution of Russell Westbrook’s Second Chances

Westbrook put back up less than half of his rebounds, which indicates he was a ‘cycle-the-offense’ style of player. While his shooting numbers suffered greatly on second chances at 37-72 (.514) 2P, 1-4 (.250) 3P, .521 eFG%, Carmelo Anthony and Steven Adams benefited greatly.

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Distribution of 2017-18 Second Chance FGA courtesy of Russell Westbrook.

Anthony shot a blistering 10-for-13 from the three point line en route to 40 extra points. Adams uncharacteristically made 3-of-4 free throws to go along with his 5-of-7 shooting for an extra 15 points. Only Paul George and Corey Brewer struggled to score on second chance points generated by Westbrook.

It’s a Start!

Given the nature of second chance distributions, we can start to break down what teams end up doing with their possessions. We find that Drummond is a great rebounder, but lacks the ability of DeAndre Jordan to finish baskets. We also find that Steven Adams leads the Oklahoma City Thunder into chaos as he tries to kick back out to their big three if he doesn’t have the chance to get a put-back.

We also saw how the Minnesota Timberwolves are patient and restart their offense through Karl-Anthony Towns; and how Giannis Antetokounmpo and Russell Westbrook defy the traditional “bigs” approach to becoming a rebounding specialist.

Where we’d want to go next is breaking down how other specialists open up paths for rebounding; such as the Robin Lopez types. And furthermore, what position these rebounders put themselves in before attempting to get the rebound. Think of this as an advanced way of adjusted OREB%; which would in turn give us better insight into the intelligence these rebounding specialists bring to the game.

Oh yes…

And before we leave, here’s the distribution of second chance points across the league for the 2017-18 NBA season:

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One thought on “Second Chances and the Rebounding Specialist

  1. Pingback: Weekly Sports Analytics News Roundup - October 9th, 2018 - StatSheetStuffer

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