Much has been made of the SportVu stats introduced this season. While parsing out meaningful data has been few and far between, Seth Partnow of Where Offense Happens happened to capture the first two quarterly splits for the season and noticed something interesting regarding DeAndre Jordan. Here’s what he discovered:
Aside from Chris Paul’s shoulder injury, the largest cloud hanging over the Clippers’ title chances concerns defense; specifically interior defense. “Blake Griffin and DeAndre Jordan are not enough to compete in the Western Conference playoffs,” or so goes that particular narrative. Jordan in particular has been subject to a large helping of criticism regarding his ability to patrol the paint.
Despite the Clippers’ generally solid defensive numbers (the team currently sits ninth in unadjusted defensive rating for the season per Basketball-Reference.com), interior play has been a concern; allowing the eighth most points in the paint per game and the ninth most offensive rebounds as a percentage of available rebounds. For the first 23 games of the season, the story was slightly bleaker, as they allowed the seventh most points in the paint per game in the league.
With NBA.com featuring data from the revolutionary SportVU cameras positioned in every arena, it’s possible to look in minute detail at why the Clippers’ interior defense was so porous. By the “defensive impact” numbers, of the 63 big men in the league playing more or less starters’ minutes, Jordan and Griffin ranked 49th and 57th respectively in their per minute rim protection value.
Let me back up a little and explain the methodology (more in depth here). At first pass, the most common reaction to the SportVU data is to look at “Opponent FG% at the rim” and stop there. However, I think focusing on simply the percentage of makes only tells half the story. The number of shots contested is equally, if not more important.
League-wide, an uncontested shot taken within 5-feet of the rim is scored at around 75 percent. Contested shots at the rim are scored just over 51 percent and, separating out the small percentage of these shots contested by guards and wings, shots contested by “bigs” are scored at slightly under 50 percent. So if a layup typically yields about 1.5 points, simply having a big man standing there saves the defense 0.5 points on average.
Further, the difference in opponent’s field goal percentage between the very best at-rim defenders such as Roy Hibbert (just over 40 percent) and the very worst such as Kevin Love (just under 60 percent) is about the difference between an uncontested shot and Love being present. To put it even more simply, just being big and in front of the rim has a lot of value.
Intuitively, we understand this as we know these two shots are not equal even if both happen to go in:
So, by virtue of simply challenging shots, through 24 games, DeAndre wasn’t quite as bad as his 56.4 percent allowed at the rim (10th worst among that sample) might indicate. He was contesting 8.5 shots per game at the rim, which on a per minute basis put him squarely in the middle of the pack. Between his percentage allowed and the number of contests, DeAndre was giving up about 1.25 points per game at the rim more than the average starting big man in the NBA would have. Of course, the story was worse for Blake, who was contesting the fewest shots at the rim (per minute) of any starting big, and was conceding about 2.0 points more per game at the rim than would an average big man. The only pairing performing worse over that span is Minnesota’s notoriously gravity-bound duo of Love and Nikola Pekovic.
To make a long story short, six weeks into the season, the claim that L.A.’s interior defense would prove to be their undoing looked like a reasonable bet.
Then a funny thing happened. DeAndre got better. Much better. It’s visible to a degree in his traditional stats:
He’s playing a few more minutes, fouling slightly less frequently and has upped his blocks and defensive rebounding considerably.
But diving into the rim protection numbers, the difference is even starker. I first noticed it when I ran the numbers a second time shortly after Christmas, but it was too early to tell if it was merely short-term noise or evidence of a larger trend. Now, just under six weeks from the initial sample, I took another look. And here’s what I found:
By this measure DeAndre has been more than three points per game better at protecting the paint over the recent stretch versus the start of the season. To put it another way, the difference between Jordan in the first quarter of the season to the second is roughly equal to the difference between the Clippers’ defense and that of the Chicago Bulls. To give further context, over that span, only presumptive Defensive Player of the Year Roy Hibbert and Serge Ibaka have provided more rim protection than Jordan.
Now, it’s not quite that simple; rim protection is only one component of defense. DeAndre’s improvement has been offset by deficiencies in other areas of the Clips’ defense, such as the injuries to Chris Paul and Matt Barnes, not to mention the continued struggle to find competent reserve bigs. But the improved rim protection clearly shows up in broader team numbers.
Over the first portion of the season, the Clippers were 26th in the league in opponent’s field goal percentage at the rim, allowing about two points per game over the expected average defense. Over the latest 20, they are up to 17th in this measure, allowing only about 0.25 points more than an average defense. Nothing to write home about yet, as it is far from an elite ranking. It is far superior to the start of the season, though, changing a potentially fatal downfall into a more manageable challenge. For this, the Clippers have the improved interior defense of DeAndre Jordan to thank.