How Celtics’ role players are reinforcing Joe Mazzulla’s spacing system

BOSTON, MASSACHUSETTS - OCTOBER 30: Sam Hauser #30 of the Boston Celtics reacts with Grant Williams #12 of the Boston Celtics after he hits a three point shot during the fourth quarter of the game at TD Garden on October 30, 2022 in Boston, Massachusetts. NOTE TO USER: User expressly acknowledges and agrees that, by downloading and or using this photograph, User is consenting to the terms and conditions of the Getty Images License Agreement. (Photo by Nick Grace/Getty Images)
By Jared Weiss
Dec 7, 2022

Joe Mazzulla’s core values have been taking shape over the first month-plus of the season, with the topic of spacing coming up on a nightly basis.

But he doesn’t talk about common terms in the traditional sense. Spacing was a concept that moved to the forefront of the public lexicon during the five-out revolution in the early 2010s, as bigs started to become 3-point shooters and teams looked to open up the paint as much as possible.

Advertisement

Then going four out, one in came back in vogue as bigs started rolling more or lurking in the dunker spot behind the hoop. Boston has embraced this since Al Horford — a pick-and-pop specialist — initially departed and Rob Williams ascended. Daniel Theis mastered the Gortat, rolling across the paint and sealing off the defender(s) so his pick-and-roll partner could waltz all the way to the rim. The Celtics break that out every once in a while, but they’re now using the big a little differently to disrupt the paint.

When the Celtics swing the ball to the corners and attack, the center is getting in the way on purpose. It’s a recognition of the growth of players like Grant Williams, who this year has gone from just being able to attack a closeout to thriving against them.

Last season, Grant Williams would up fake, dribble toward the midrange and then pass it to a shooter on the elbow. From there, he would fill a spot on the perimeter and be ready to launch. But even as he improves his handle enough to have a legit shot at going to the rim, players like Luke Kornet and Blake Griffin are standing right under the hoop.

It’s a sign Williams is turning into an actual wing, because the scheme is betting he can get deep into the defense and still make rim reads.

How the gamble works is the big stands right under the net as Williams begins to drive, keeping his man in position to protect the rim. That means he would be open under the rim, so another defender has to help off a shooter to cover the big. Because the player closing out on Williams is going to be either trailing him or just out of the play into the corner, Williams has three defenders engaged at the rim and one open teammate somewhere on the perimeter. That can leave a lot of space against a hard closeout defense like Toronto’s.

In the first clip, Williams loses Fred VanVleet and draws Gary Trent Jr. and Pascal Siakam at the rim, leaving a vast amount of space for Marcus Smart on the Scotiabank Arena floor. He draws hard at the rim, even though he’s going right toward Griffin, just to sell the rotating Siakam on the shot.

Then he veers hard to his right on his gather, making it easy to step past the help and fire the pass to Smart. Notice how Jayson Tatum is pointing to Smart once Williams makes the move, then immediately starts backpedaling with his hands up. He knows that Smart knows.

Advertisement

That’s why this offense can operate so seamlessly without play calls. Their continuity is yielding a form of on-court telepathy.

So when Mazzulla talks about spacing, he doesn’t mean large swaths of hardwood to roam. He means precise alignment, even in cramped zones of the floor, to open up all these reads built into the system. Now that his rotation is almost entirely players who can put the ball on the floor and see all those reads, it’s working better than anyone else in the league.

Hauser holding it down on his own

Early in the season, there was a sense that Boston’s defense had taken a step back and was lagging behind the offensive revolution taking place across the court. Part of that was the deep drop the Celtics bigs were employing to invite drivers into the paint and keep help defenders spaced out. The big-man rotation was a work in progress.

But since the two losses in a row in the second week of the season to the Bulls and Cavaliers, respectively, the defense has been just about where they could hope without Rob Williams. They’re 14-2 over their last 16 games and have a 110.6 defensive rating, seventh in the league over that span.

As the Celtics’ defense tightened up, teams have taken to mismatch targeting more, with Sam Hauser a frequently presumed weak point. While Boston ranks last in the league in points per possession (ppp) defending isolations, Hauser has been one of the few bright spots. He’s been put on an island 37 times, per Synergy, but has only allowed 34 points.

What makes him effective? The context inflates his ability a bit, as a lot of the isolations come from players who generally wouldn’t try to go for it against more reputable defenders. But even versus star players, he doesn’t look out of place. So while his shooting and movement have been his calling card, his defense has kept him in the rotation.

Against De’Aaron Fox, he can flip his hips smoothly enough to not bite on his crossovers and then tightly contest the stepback 3 without fouling. When Brandon Ingram tried to barrel through him, Hauser took a wide swipe at the ball to force Ingram to pick it up without a foul, then anticipated the spin back to get a hand in Ingram’s face. They’re both shots these stars hit often under duress, but he knows the personnel scouting report well enough to make them as uncomfortable as possible in those scenarios.

Advertisement

Even with Dejounte Murray scoring on that last one, later in the video above, Hauser was in position to get a hand on the shot but seemed to pull away so he wouldn’t possibly foul while Luke Kornet had rotated into the perfect spot. Hauser rarely goes for the block. He goes for the miss. He gets it.

Aside from one Kevin Durant blow-by — it’s happened to everyone in the league — he has been a stonewall when he’s defending in space. His iso defense is a nice litmus test for what makes a great scorer, as usually only top players who can combine speed and guile can get to a position where they can narrowly score on him.

When Siakam cleared him out, the Raptors star bumped Hauser hard enough to send him deep into the paint, allowing Siakam to get to the restricted circle for his turnaround jumper. When Bradley Beal took him to the corner in the clip below, he played Beal too hard to the baseline and gave Beal just enough room to bump him and sneak in a finger roll.

That’s the difference between a good defender like Hauser and a real stopper at the wing like Jaylen Brown or Tatum. For a second-year player who was on a two-way contract last season, it’s a big step forward. If he can keep this up as the Celtics get fully healthy, his job is going to be even easier.

But with solid technique, good balance and just enough power to handle most players, Hauser looks like he’s going from a two-way player on the payroll to a two-way athlete on the floor.

(Photo: Nick Grace / Getty Images)

Get all-access to exclusive stories.

Subscribe to The Athletic for in-depth coverage of your favorite players, teams, leagues and clubs. Try a week on us.

Jared Weiss

Jared Weiss is a staff writer covering the Boston Celtics and NBA for The Athletic. He has covered the Celtics since 2011, co-founding CLNS Media Network while in college before covering the team for SB Nation's CelticsBlog and USA Today. Before coming to The Athletic, Weiss spent a decade working for the government, primarily as a compliance bank regulator. Follow Jared on Twitter @JaredWeissNBA