The diminishing value of offensive boards

January 4, 2017 by J.H. Yeh

We previously discussed how teams are valuing 3-pointers to win games due to the higher returns — a convincing sign that the modern basketball games are evolving. In this article, I will go in depth on another aspect of the game that is also going through a change.

In today’s NBA, teams, thanks to the advent of analytics, are shooting 3-pointers at an unprecedented rate, which facilitates the pace of the game. And the result? More rebounds. However, due to the changing dynamic in basketball, offensive rebounds have become the victim of the evolution of basketball. As teams are now hoisting many 3s, which often results in long rebounds that can turn into easy transition points, more and more NBA teams have abandoned the old-school strategy employed before 2000s. Back then, with literally no emphasis on floor spacing, teams heavily relied on crashing for offensive rebounds to win over second chance points — and ultimately, to win games. 30 years ago, in the 1986-87 season (not shown below) back when shooting 3s was non-existent (teams only attempted 4.7  3-pointers and made only 30.1% of them), players would pound the paint for offensive rebounds because that was the best way to earn an extra possession and potentially a couple extra points. As a result, basketball back then was a big men’s game as rebounders were highly valuable.

As the game progresses, along with the arrival of analytics that favors 3-point field goals over mid-range jumpers, firing shots from beyond the arc has become the norm since this is how today’s coaches run their offense. Correspondingly, with the number of rebounds go up due to the high quantity of 3-point attempts, many of these rebounds bounce far from the rim which allow opposing team’s guards to catch them and quickly score through transition by either driving to the paint or attempting a pull-up 3-pointer. The result is the diminishing value in offensive rebounds because teams rather prevent the opponent from scoring in transition and getting into rhythm than extending their own possession by rebounding offensive boards and making an additional basket. The table below shows the change in rebounding in the past 20 seasons. Note the increase in total rebounds forms a sharp contrast with the decrease of offensive rebounds. In the past 20 years, due to the faster pace of the game (thanks to the influx of 3-point shooting), total rebounds have gone up by 2.6 while offensive boards have gone down by 2.4. This validates the fact that teams are more concerned about defending transition points than rebounding for a second chance opportunity. It also shows that offensive boards are not being valued as much as it used to be and games are won by floor spacing and solid defense as oppose to grabbing offensive rebounds. Furthermore, teams are grabbing offensive rebounds at a historically low rate at 23.6% — a 7.3% drop from 1986. Coincidentally, while at the same time, defensive rebounding rate has gone up also by 7.3% (from 69.1% to 76.4%) because of heavy emphasis placed on defense and creating offensive possessions to score (by terminating the opponent’s offensive possession). This information is as of January 4, 2017.

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These numbers further reflect that the addition of  3-point shooting has changed how the teams value offensive rebounds as NBA teams today see that quickly getting back on defense is more important than collecting offensive rebounds. Preventing easy transition points is viewed as the number one defensive assignment after the conclusion of an offensive possession because failing to guard transition points can usually allow the opponent to go on a multiple-points-to-nothing run that will shift the momentum of the game. This explains why for teams like the San Antonio Spurs and the Los Angeles Clippers, who usually feature two bigs, they only station one big man under the basket for offensive board, and before the ball descends, the second big man, along with the other three players, is running towards the half court, preparing for defensive setup to stop any potential transition scoring.

In today’s NBA, rebounding is the second most important skill next to 3-point shooting and floor spacing. But when it comes to rebounding, teams are focusing specifically on defensive rebounds. This year’s Chicago Bulls are a prime example of an NBA team that plays like a team from the 1980s and 1990s. With a starting lineup that features Jimmy Butler, Dwyane Wade, Rajon Rondo, Taj Gibson, and Robin Lopez, the team is currently ranked first in the league in offensive rebounds, offensive rebounding rate, and total rebounds, thanks to the offseason acquisition in Wade and Rondo, who are terrific rebounding guards with career rebounding averages of 4.8 and 4.9, respectively. Not to mention Butler’s good rebounding skills, the Bulls have transformed into an old-school, rebounding team who doesn’t shoot 3s and only rely on mid-range touches and drives to the basket. Lopez and Gibson have never made a 3-pointer in their combined 17 seasons together and all three Wade, Rondo, and Butler are collectively shooting 33.0% (90 for 272) from the 3-point territory. Overall, the entire Bulls team ranks dead last in 3-point attempts and is the only NBA team that shoots less than 20  3-point shot per game.

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With no ability to space the floor and investing too much focus and man power on offensive rebounds, the Bulls team struggled on both ends of the floor in recent weeks and is hovering about at the .500 mark despite a roster that features three all stars. The Bulls have elite players in Wade, Rondo, and Butler at the wing but all three of them are not the best complement to aid the team in floor spacing and transition defense. Therefore, explaining Rondo’s recent benching in what head coach Fred Hoiberg called “a basketball decision.”

Similarly, Joe Dumars’ 2013-2014 Pistons that featured ultra-big starters in Josh Smith, Andre Drummond, and Greg Monroe, were ranked first and third in offensive rebounds and total rebounds, and 22nd in 3-point attempts (better than Bulls, but still far below the league average). That year, Joe Dumars’ carefully constructed old-school basketball team finished the season with an abysmal record of 29-53 in the weak East. Interestingly, the playing style of the 2013-14 Pistons is the exact same playing style in 1989 and 1990 — when the Pistons won championships and Dumars flourished. This validates the notion that the individuals who are the last to be receptive towards analytics are the ones very successful without it.

In summary, like mid-range shots, offensive rebounds are seen as less valuable in today’s NBA. At almost every occasion when a team shoots the ball, its players quickly retreat from the basket — a strong indication that suggests less commitment to offensive rebounds and more commitment to transition defense.

— J.H. Yeh

(all graphs are created by me, and all sources of stats are courtesy of NBA.com and BasketballReference.com as of January 4, 2017)

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