The Celtics are 4-2 so far, right about where I expected them to be. However, it can be argued that their two losses easily could have been wins. They fell apart against the Chicago Bulls, in part, because they allowed a ton of dribble penetration and second-chance points. A pair of late offensive rebounds cost them against the Cavaliers, turning a regulation-time win into an overtime loss.
Giving up offensive rebounds has been an annoying issue for the Celtics over the first six games. The Celtics rebounding overall has been an issue, leading to them having the fifth-worst rebounding percentage in the league. Their defensive rebounding percentage (48.7%) and offensive rebounds allowed per game (10.8) put them square in the middle of the NBA pack. And while tracking data can be somewhat iffy, the five box outs per game it has registered for the Celtics is a fraction away from the NBA’s worst. You’ll see that in these clips. There is A LOT of turning and watching shots. There is very little boxing out.
Sometimes it is just as simple as putting your body on someone and grabbing a rebound.
So what’s going on here? Do they miss Robert Williams that much?
I looked at every offensive rebound the Celtics have given up over six games to find out.
Let’s start with this: teams are going to get offensive rebounds no matter what teams do. Even the worst team at it in the NBA, the Sixers, get about 21% of the available offensive rebounds (Doc Rivers values retreating on defense instead of crashing for putbacks). The Raptors allow the fewest defensive rebounds in the league and even they give up 7.3 per game.
There are going to be a few lucky bounces that we’ll have to dismiss as well. Every game is going to have a weird bounce, or an airball that goes the other way. Every once in a while a Celtic blocks a shot that the opponent catches, which goes down as an offensive rebound (as long as it’s a shot, it doesn’t matter if it hits the rim, the backboard, or someone’s hand. The next person that catches it is credited with a rebound).
In a couple of these examples, you’ll see some guys get their own rebounds, which is tough to combat. For example, Nikola Vucevic had 10 offensive rebounds against the Celtics and he got seven of those in three possessions. That doesn’t excuse why he was in position in the first place, but then getting multiple offensive boards off his own misses makes the overall numbers look worse.
The Celtics are, though, having some repetitive issues that give opponents too many second chances.
PICK SETTERS
The Celtics have had trouble defending the pick-and-roll. Most of the time, that leads to good shots and a barrage of made baskets, but the Celtics have been burned from time to time by the roll man breaking free to the rim. Chicago benefited from the most egregious examples of this.
Marcus Smart and Al Horford are both going with the ball handler, so that leaves Vucevic to keep marching toward the rim. By the time the ball comes off, Horford and Smart are both stuck too far under to make any real play on the ball.
Horford drops, Jayson Tatum sticks to the pick, and Vucevic does a good job of sealing him off.
What should happen here is Derrick White sliding in to box Vucevic out and Tatum keeping an eye on the corner guy in case he crashes. White actually gets a hand on the ball, but had he been in position, he could have either gotten the rebound or drawn a foul on Vucevic.
This is 100% poor effort. A simple box out, even from a guard on a big, would have changed this possession.
This one too:
The Celtics sticking with their drop coverage puts a lot of pressure on others to pick up the slack when a guard chases over the top of a screen. Smart sticks to the pick here and Grant Williams decides he’s going to help on Zach LaVine.
At this point, Smart has to understand the floor. There has to be a warning going off in his head that tells him, in not so many words, “three of us are looking at this one dude, and I just left his partner. I should probably figure out where that dude is.”
That's awareness, which I know all these guys have. They just haven't been demonstrating it enough. The good news is things like this are incredibly fixable.
JUST FLAT OUT LOSING GUYS
This is another issue the Celtics are having a real problem with. This goes back to the same recognition I just mentioned with Smart. A guy seems to be out of the play and then he’s suddenly at the rim.
Horford is just ball watching. When the shot goes up, he just needs to glance back to see if anyone is doing what Rui Hachimura did in this clip. It’s just a quick glance to account for anyone trying to sneak in. He’s certainly not the only guy making this mistake from time to time.
Cole Anthony is Malcolm Brogdon’s responsibility here. Watch Grant Williams closely as he gives that quick glance back that I’m talking about just as the shot goes up. He accounted for his man, so he doesn't think anyone is chasing him, but Anthony snuck in just out of Grant’s sight.
That's Kyle Lowry sneaking past Tatum.
Jimmy Butler also caught Tatum in that game.
Here are the painful ones. Caris LeVert burned Jaylen Brown with a corner crash. Notice, by the way, Brogdon giving Evan Mobley the glance. That's especially upsetting considering what happened next.
Brogdon’s in the same spot, and he has LeVert. He JUST toasted a teammate with a corner crash … and you JUST did the right thing by giving your guy the glance to make sure he wasn’t crashing … that makes this lapse especially egregious.
Just look at Horford giving Brogdon a look in the middle of the play. He was so pissed in the moment that he was a step slow challenging the shot. Horford was very angry at this play, and rightfully so.
These types of plays are sins against basketball, and the Basketball Gods punish them harshly. This isn’t college basketball with one or two games a week with shorter games, so I know there are times when the turn-and-look is just a matter of conserving energy. There are plenty of possessions where teams don’t crash, so guys don’t have to go crazy searching for bodies to box out.
At the same time, that little glance will just confirm that it’s ok to just turn and grab the board. There are times where that glance is a little more necessary, like those late-game situations where the Cavs were down and LeVert saw a chance to extend possessions.
HELP, WITHOUT THE RECOVER
Here’s something along those same lines that's happening from time to time.
This is a byproduct of dribble penetration. The Celtics have been giving that up more than we’d like to see. When a player comes over to help, the Celtics have a tendency to leave the helping player’s man open, and these kinds of rebounds are happening.
The Celtics simply need to be better about when they help, and then the player who’s receiving the help has to be better about recovering to the helping player’s man. It’s basically a switch, and it needs to be recognized to prevent giving up second chances.
SIDE NOTE:
I’m not a fan of this weird contest by Luke Kornet. Look at him jump past his man twice.
The first results in a Jarrett Allen tip that kept the possession alive, and then he was bailed out by a weird bounce over the rim after being out of position again.
I don’t think this affects anyone’s shot, but it does pull him out of position to box out his guy.
CONCLUSION
I don’t think I need to tell you what the first adjustment here is. I think all these clips kind of confirm that there is too much turning and watching, and not enough of the little effort plays that can prevent a lot of offensive rebounds … give a look over your shoulder to see if someone is coming. If someone is, get in front of him. It’s pretty simple.
On top of that, there needs to be better awareness on the floor: who’s helping, who has been left alone, and where is that player right now? A little more focus can go a long way.
And one last note: when there is a box out, be aware of the dynamics of what’s happening.
Tatum is aware of the player next to him, but he’s still in poor rebounding position because of where the shot is coming from.
Dennis Rodman was one of the best rebounders in the world because he understood angles and where the ball was most likely to go. Long shots tend to produce rebounds on the opposite side of the rim that the shot came from, so Tatum should actually be trying to drive his guy further to the baseline, or he could even spin to go back-to-back because there's little chance that ball will come off the front of the rim.
These little things are keys to good rebounding. Good position on one shot is bad position on a different one. A little bit of work understanding the angles a little better will also help.
But the effort and recognition stuff is the most important. At the top of this piece, you saw the difference between the fewest offensive rebounds per game and what Boston is giving up is just 3.5. That six points or so already cost the Celtics a loss against Cleveland, so there's real incentive to bridge that gap.
But also, that's not the widest gap in the world to bridge. The simplest fixes can help Boston’s rebounding. The effort it takes to simply impede someone’s progress to the rim can make a big difference in a game. It can also help team chemistry, because as you saw with Horford on the LeVert rebound, one person’s lack of effort can piss a teammate off and make other people look bad.
The rebounding issues are very fixable, and they can help shore up a defense that's been a little too shaky, too often.
“Just continue to stress all five guys have to rebound,” Joe Mazzulla said of his team’s propensity for giving up second chances. “It’s something that we talked about. We just can’t have guys leaking out, can’t have guys in the paint. And how it’s everybody’s responsibility. And we just have to make that commitment.”
