The Boston Celtics offense has become the fat Elvis of the NBA. The once shimmering glory, a phenomenon that put other phenomena to shame, has given in to indulgence and bad habits, putting forth a product that has become barely passable.
Barely passable, in fact, can also be a sort of explanation for what is happening to the Celtics lately.
As I noted yesterday, The Celtics had been leading the league in 3-point shooting, and now they're down to fourth. Their offensive rating had been up over 120 for a long time, now it’s down to 116.8. Over their last five games (four losses), Boston has the league’s worst offense (101 offensive rating), four points below the next worst team.
What happened?
The simplest way to put it is they're getting away from what worked. They have fallen victim to one of the classic blunders. The most famous is never get involved in a land war in Asia, but only slightly less well known is this: Never fall in love with 3-pointers when making them is predicated on attacking and passing.
The numbers are not pretty when they're broken up between the pre-road trip Celtics and the team we’ve seen in the last 8 games.
Before the trip, Boston threw 279 passes per game. 27.4 of those went for assists and there were 47 others that were potential assists. The assists created 73 points per game.
In the last eight games, Boston dipped to 270 passes per game. Only 23 of those went for assists and 45 were potential assists. The assists created 59.3 passes per game.
Obviously, shots have to fall to get assists, so the number of assists falling makes sense. A team that goes cold will have fewer assists in general. But the drop in potential assists is a bit damning, even if it is only by a couple.
The pre-trip Celtics took 41.7 3-pointers per game, a number that has jumped to 42.4 in the least eight. But the drop in assists and potential assists shows more shots are going up without the requisite ball movement.
The Celtics used to shoot 12.9 for 30.5 on catch-and-shoot attempts per game (42.2%). In the last eight games, they’ve made 9 for 29.4 (30.6%). Not only are they cold, making nearly four fewer catch-and-shoot attempts per game, they're taking fewer.
Their pull-up 3-pointers have jumped from 10.5 to 12.4 per game but the percentage has dropped from 34.4% to 32.3%
They have insisted, at least publicly, that the shots they're getting are good, and they should keep shooting them. There is some validity to that, but there is also an issue there.
The numbers support them in that regard. They are taking 21.3 wide open 3-pointers according to NBA tracking data (wide open is classified as a defender 6+ feet away), a 2.3% increase over the last eight games. Their percentage, though, has dropped from 44% to 32.9%, a stunning decline on a desirable shot. They’ve also cratered in open shots (a defender 4-6 feet away), falling from 40.1% to 25.4%.
In the most basic sense of things, you want open and wide open shots in basketball. The worst team on wide open shots in the NBA, Charlotte, is shooting 33.5%. The worst shooting team on open shots is Oklahoma City at 29.1%, so the last eight games have been worse performances than the absolute worst-shooting teams in the league.
That's more than a regression to the mean. That's a ridiculous cold streak that will re-correct itself. So when Joe Mazzulla says “If you’re open you gotta shoot it. And we’re open, so I'm not going to tell someone who's open not to shoot it. They have to have the confidence to shoot it, and then you just got to shoot it,” he is right … to a point.
This is why I suggested earlier that Mazzulla might be saying more to his team privately. He’s not going to crush his team in the media like his predecessor. He’s much more Brad Stevens than he is Ime Udoka.
The process of getting to the open shots has some impact on whether those shots fall. There's more to the shot than just taking an open one. There are other players on the floor who need to feel involved, who need to move, and who need to touch the ball. The less often they do that, the less likely they are to make shots.
Paint touches are a big driver for open shots. It collapses defenses, forces overreactions, and creates opportunities all over the floor. Boston’s pre-trip paint touches resulted in an assist percentage of 7.7%. That number has dropped to 4.7%. Their paint-touch turnover percentage has jumped from 4.1% to 6.0%, so the Celtics are passing less out of their paint touches, mostly because they're coughing it up more often.
This jibes with what we’ve seen. Drives have gotten deeper and help defenders are coming over more often. Celtics drives aren’t triggering the type of ball movement we’ve seen, as often as we’ve seen it. The turnovers aren’t just a problem that leads to transition opportunities, they are preventing the passing that gets everyone involved.
The ball is also being held more often. Boston is taking 1.5 more 3-pointers per game after dribbling the ball seven times or more. That means a couple times a game, someone is walking the ball up the floor and jacking it up. We can say that having it happen a couple of times is not the biggest deal in the world, but the cumulative effect of all of these things points to the same conclusion.
The Celtics aren’t moving the ball as much as they used to. They are taking two more 3-pointers per game after holding the ball six seconds or more. Considering that's 25% of the shot clock, that's a long time for those kinds of shots. They shoot 29.3% on those shots, by the way. On those shots with seven or more dribbles (which probably overlap with the six-second touches) they are at 25.8%
The good news with all of these numbers is that they're very correctable. This is only an eight-game sample, and we can argue that the length of the road trip was a major factor in this. The fatigue by the end of it was real, and snapping out of the fog of that has proven difficult.
But this also is a visit from the ghost of Celtics past. We’ve seen these things before, so in some ways, this is a frightening glimpse onto old bad habits. The problems here can be fixed on Wednesday night against Indiana, but it is certainly easy to see why there's doubt creeping into people’s minds. Have they learned from their history, or are they doomed to repeat it?
The numbers tell a story, but the Celtics can write the next chapter. The question is whether we’ll look back on this as a footnote of the season, or a turning point.
