Looking at the breakdown of the game by play type, Boston ran somewhere in the neighborhood of 20-25 pick-and-roll sets, a significant number below their average. That’s notable in itself, but looking at the distribution of the Clippers’ defensive coverages in those possessions, one thing stands out:
The Clippers rarely trapped the ball-handler.
As you watch the possessions in sequence, you see the Clippers defense employ more hard hedges. They were much more concerned with patrolling passing lanes and backpedaling to make sure that the Celtics’ screeners were picked up on the roll. This strategy might have yielded a few more shots at the rim for Rajon Rondo (he had nine such opportunities), but overall the Celtics were much less active in the half-court than they normally are.
The Clippers have traditionally been a defensive squad that’s run a lot of perimeter traps at opposing ball-handlers. We can attribute some of that to a lack of defensive flexibility. The Clippers don’t have bigs you can switch onto smalls, though that should change once Blake Griffin is healthy.
I’m not an ideologue on pick-and-roll defense. Context is very important. Mike Woodson will tell you that Atlanta’s defense switches so readily because they have the personnel to do so, with versatility at the 2, 3 and 4 — to say nothing of a 1 you’d like to get off the ball as soon as possible. The Clippers, given their current personnel, would be foolish to switch a lot of PNRs. But if you have guys who can guard multiple positions, it makes sense to show that look to defenses at strategic moments.
I can’t help but wonder if last night’s defensive success against Boston might have shined a new light on how the Clippers can continue to improve defensively. They’ve never been a horrible defensive pick-and-roll team, but they also have the capacity to get better.
UPDATE: In speaking to Mike Dunleavy today, he mentioned that the help off the perimeter (from Tony Allen’s man) played a big role in the Clippers’ ability to defend Boston’s pick-and-rolls Sunday evening. The video certainly confirms this.

