Stat geeks, cover your eyes… you're not going to like what you're about to see.
Actually… scratch that. Open your eyes. Focus your attention on this post. Because it is the proof that the numbers lie… or at least don't tell the whole story. Sometimes, you need to look beyond the numbers and find out WHY they are what they are.
This was born from yesterday's Dump… where we quoted the argument that the Celtics "had the Celtics had the lowest offensive rebounding rate in the league this year. Historically, that would mark them as possible playoff underperformers."
Yes. The Celtics are not a great offensive rebounding team. But that, dear number-cruncher, is part of the plan. They don't grab a lot of offensive rebounds because they don't care to. They only crash in certain situations, and are happy to simply retreat most others. Here is the proof, courtesy of the Celtics two easiest wins against the Knicks.
Watch the first three shots go up. Long two's (which the Celtics hit at an unreal rate… another thing that drives the stat-nerds nuts). And in every situation just watch the rest of the Celtics gaze at the shot and start to run back before it even reaches the rim. The only player who sniffs around for an offensive board is Rajon Rondo at the :17 mark. The only player in that entire video (aside from Rondo creeping in to maybe steal a board) to try to get a rebound on a long jumper is Nenad Krstic. I'll attribute that to old habits. At 1:55, KG goes to the board, but it's on a short jumper.
Watch in the instances where we let the play run. Look specifically at the 2:28 mark when Jeff Green takes the free throw line jumper. Everyone except for Rondo retreats. New York grabs the rebound, pushes it out to Bill Walker, and he's met by a wall of defenders by the time he gets to the free throw line. They run a little pick and pop and Walker tries to drive, but ultimately it's a missed shot.
The Celtics retreat by design on long jumpers because that's part of their transition defense. Long jumpers produce longer rebounds. If everyone's crashing the boards, the run a great risk of those jumpers flying over their heads, and leading to fast break opportunities. KG crashed on the short jumper because those tend to just fall off the rim… and you can try to tip those in without much risk.
Let's look at it again in Game 4
The trend continues with the Celtics retreating on long jumpers. When Rondo attacks at :28, KG sticks around and gets the put-back.
The few instances where the Celtics hang around on long jumpers is when they're already in position (like Krstic at 2:35).
What happens when the C's get caught behind the ball? At 3:23, KG launches a long two. Stop it at 3:25 and count how many Celtics are behind the play when a Knick touches it. I'll help you: it's four. The result of the play? A Carmelo Anthony breakaway dunk. At 3:32, Paul Pierce takes a shot and instead of retreating, they get lazy. Melo peels off and its another breakaway.
The Boston Celtics, by design, sacrifice offensive rebounding so they can just play defense. They rely on their ability to hit shots (they had a 51.89 eFG%) and were a league best +4;97 in eFG% differential. They hit their shots, and they force their opponents to miss. They were 5th in the league from 16-23 feet… so they feel good about making the long jumpers more than most teams.
Meanwhile, on defense, the Celtics gave up the 5th fewest shots at the rim (3rd lowest percentage at 60.8%) and the 3rd fewest shots from 3-9 feet (12th lowest percentage at 38.7%). By contrast, the Celtics gave up the 3rd MOST 10-15 foot jumpers, but the 2nd lowest field goal percentage from that spot (35.9%). They were in the middle of the pack (16th) in 16-23 foot shots given up, but allowed the 3rd lowest percentage (37.1%).
That's a lot of low percentages. That must mean there are a lot of rebounds available on that end. And that would explain why the Celtics are NINTH in defensive rebounding rate (74.68).
Yes, the Celtics are a top 10 team on the defensive glass.
The Celtics willingly sacrifice offensive rebounding, get back on defense, and force teams to take lower percentage shots rather than give up easier shots in transition or closer to the rim (except for the occasional crash by Rajon Rondo, who can gamble that way because he's (a) fast enough to get back and (b) not defending the rim anyway). They clean up a large percentage of those defensive rebounds and get back to work on the offensive end where they shoot a higher percentage than most teams.
So the next time people throw an offensive rebounding stat in your face to discredit the Celtics, throw all those numbers at them. Numbers can lie if you don't know why the numbers exist.
Big thanks to Jay, a.k.a. MrTrpleDouble10 for compiling all the video evidence.