In news that broke yesterday, Nerlens Noel will be forced to sit out the remainder of 2013 due to an ACL tear suffered in Tuesday night’s game against Florida. While season ending injuries are always depressing, it’s even more deflating knowing it happened to a kid so unanimously loved in the community. It certainly doesn’t feel right discussing something as trivial as a game when someone’s career has been jeopardized, but unfortunately, the season will continue without the stellar big man. They say never follow a legend because you’ll never live up to the expectations, but that’s exactly what Willie Cauley-Stein will have to attempt in the coming weeks. It certainly won’t be easy, but this job belongs to Cauley-Stein now. Of course, this leads many to question what kind of defensive drop-off Kentucky will experience as a result. I pondered that same question myself. Because of this, I’ve done some research using Kenpom.com’s advanced player statistics, estimating what kind of drop-off we could be experiencing on defense.
The first thing to note; Kenpom.com uses individual player percentages and not the regular raw totals that you’ve probably grown accustomed to over the years. Because of this, I’ll translate the numbers into per-game totals once calculated. Secondly, I’ll be making three general assumptions in order to keep the experiment unbiased. The assumptions are number of opponent two point attempts, number of opponent possessions, and number of available defensive rebound opportunities. The numbers I’ll be using are 40 opponent two-point attempts, 68 possessions, and 35 potential rebounds. These are totals typically experienced in a 2013 Kentucky game. By holding these numbers constant, I’ll be able to make a fair estimate of the potential drop-off. Finally, I’ll hold their minutes constant at 80% of total minutes played. The below table contains what Noel and Cauley-Stein “should” accomplish in those theoretical constraints.
**All calculations were made assuming that both players logged 80% of team minutes.**
The above chart should confirm two things we already know. One, Nerlens Noel was a really, really good defender. Two, there’s a sizable statistical drop-off between Noel and a defender who isn’t as talented. But unlike before, we know what to reasonably expect from Cauley-Stein when he anchors the defense. Assuming that opponents attempt 40 interior shots, have 35 offensive rebound opportunities, and possess the ball 68 times, we can expect a 1.7 per-game drop-off in blocked shots, a 0.9 per-game fall-off in steals, and a 1.2 per-game loss in defensive rebounding. Cauley-Stein has also proven to be more foul prone, getting whistled 4.2 times per-40 minutes, one more than Noel. These numbers alone are petrifying.
First, know that this experiment was purely done to measure the probable statistical loss when Willie replaces Nerlens. Some of the Kenpom data was calculated with both players on the floor, so that assuredly shifted the final numbers in some shape or form. It’s also worth mentioning that these numbers don’t reflect the possessions that Noel altered with his presence alone. And finally, there’s no doubting the emotional benefit that Noel served this team, so consider that as well. But when solely considering the numbers, the fall-off should affect around four statistical possessions a game. It may not seem that significant, but four possessions could make or break our tournament hopes at this point. Even though Cauley-Stein is a very capable defender, he’s unfortunately not Nerlens Noel. Nor is anyone. While it’s unfair to expect Nerlens-like defensive production out of anybody, it’ll have to happen for NCAA hopes to stay alive.