The Los Angeles Clippers have played 26 games this season. They are 17-9 in those 26 games. The expectation at the beginning of the season was that they would be a very good offensive team, and might struggle on the defensive end. When the season began the statistical data supported that notion perfectly. The overall impression of the Clippers as an offensive juggernaut that can't actually stop opponents remains, but that data have changed significantly.
Breaking the Clippers season into two convenient 13 game samples, a picture emerges of two very different teams.
So who are these guys? Do they have the third worst defense in the league, as the data from the first 13 games tells us? Or do they have the single best defense in the league, according to the data from the most recent 13 games?
The offense has been worse -- by 3.3 points per 100 possessions, which isn't a huge difference, but is still a concern when you consider that the Clippers schedule has been much softer during the second set of 13 games. On the other hand, the defense has been almost 10 points better per 100 possessions, which is the difference between the best defense in the league and one of the very worst. That's just crazy. Consider the stories that might have been written about the Clippers had they been leading the league in defensive efficiency a month into the season.
Is there any reasonable explanation for all of this? It probably depends on your definition of reasonable, but here are some possible explanations I can think of:
1) Randomness. Randomness happens. We don't like to admit it as human beings, and sports people (fans and sports professionals alike, especially coaches) REALLY don't like to admit it, but sometimes things just happen. Maybe opposing offenses made an unusual number of shots against the Clippers in the first 13 games, missed an unusual number of shots against them in the next 13 games. It happens. It is my belief that this is the single biggest factor in the diametrically opposed profiles you see in the table above. Random sh!t. But that doesn't mean there aren't other reasons also.
2) The schedule. The Clippers played a whole bunch of good offensive teams in their first 13 games, including Miami, Houston (twice), Oklahoma City (twice) and Golden State. The second set of 13 games came against some bad (and badly damaged teams). I actually wrote about this very thing prior to the Indiana game. Note that this could explain a large part of the change in their defensive numbers, but it doesn't really explain why their offense has been worse, since their offense should have gotten better against bad teams.
3) J.J. Redick. Redick was injured in the first half of the 17th game of the season, so the first sample of 13 games includes a healthy Redick in every one, while the second sample has nine and a half games with no Redick. Add in the Matt Barnes and Reggie Bullock injuries (not to mention Chris Paul's hamstring), and the Clippers wing rotation has been a disaster for that second group of games -- but Redick seems to be the linchpin. His off ball movement is crucial to the Clippers offense. It shouldn't really be this crucial it seems to me, but there it is. (The pessimistic side of this coin is the possibility that Redick's presence makes the Clippers a much worse defensive team, his absence makes them better. I'm hoping that's not the case, but it's one way of looking at things.)
4) Antawn Jamison for Byron Mullens. Antawn Jamison sat out the first 14 games of the season and has been the first big off the bench for the Clippers in the last 12. If you're looking for the single factor with the highest correlation to the Clippers defensive improvement, this is it. Of course, the idea that playing Jamison would make a team better defensively flies in the face of conventional wisdom about Jamison, a noted non-defender. But Mullens is actually worse, so it may have been addition by subtraction just to not have Mullens appear in games.
5) Time with Doc Rivers' defensive system. If you want the glass half full (or even cup overfloweth) interpretation of the data, it's that the Clippers players took some amount of time to understand, embrace, internalize and master the defensive principles that Doc Rivers implemented when he took over the team. The first few weeks they were still learning, they got lost, they made mistakes and those mistakes made them into a terrible defensive team; now that they get it, they're a great defensive team.
I'm not here to tell you exactly what is going on primarily because I don't know. The data itself is certainly interesting though. If you want to spin this as hopefully and optimistically as possible, then the defense is in fact among the best in the league now that the players get what Rivers wants and will only get better as they get more and more comfortable. Meanwhile, the Clippers will get Redick back with three full months of basketball left, return to being a great offensive team, and reach elite status (at least from a statistical standpoint) in the second half of the season, with a top five offense and a top five defense. Not much of that passes the eye test, that tells us that the Clippers have not been a very good team these past 25 days, despite their elite defensive numbers -- but maybe our eyes, more accustomed to pretty offense, have been deceiving us.
Or maybe it's all just some random sh!t that happened.