How Will The Celtics Change?

The Celtics have been good enough to win the Finals for the last half-decade, but they’ve never won the prize. Brad Stevens decided that major moves were needed to do better than “good enough.”

To recap: fan-favorite point guard Marcus Smart was traded away to the Memphis Grizzlies, and versatile defender Grant Williams was shipped to Dallas. To replace them, the Celtics brought in the OG unicorn, Kristaps Porzingis.

For better or for worse, the Celtics now appear — on paper — to be locked primarily into a two-big lineup. (In reality, history suggests that at least one of Porzingis, Al Horford, or Rob Williams will likely be in street clothes at any given time, but we will proceed under the assumption of health.)

Although effectiveness can vary, Porzingis, Williams, and Horford can all play the four or the five. Porzingis was half of some shockingly decent two-big lineups in Washington with Daniel Gafford, so he knows how to succeed in such a role.

Porzingis is a much more willing gunner than Grant Williams, and he can shoot from far behind the arc – he adds significantly more spacing to a team that thrives in it. But he also has developed into a solid back-to-the-basket passer and legitimate weapon in the paint — KP was one of the league’s most efficient and prolific post scorers. Where he used to settle for contested 15-foot turnarounds in the midrange, he’s now far more aggressive in forcing the issue and abusing mismatches:

While no offense in today’s NBA can survive on a steady diet of post-ups, Porzingis’ strength, length, and skill give the Celtics a new wrinkle to throw at opponents when the drive-and-kicks that fuel the offense sputter (as we saw happen against Miami in the postseason). 

More concretely, slotting Porzingis in for Horford or Williams opens up some exciting new plays. Picture last year’s stack/Spain pick-and-roll with Rob and Al: Rob would set the initial screen and roll, while Horford would screen for Rob and then pop to the triple line or re-screen for the ballhandler before popping. Defenses often had to choose whether to give up the alley-oop to Williams or a Horford three.

That play with Porzingis allows for far more creativity. Both KP and Horford can pop at any moment. Porzingis is an excellent screen-slipper, and the stack setup could easily become a misdirection for a KP rim run. His versatility should keep defenses on their heels.

Or picture last year’s ubiquitous, simple off-ball screen for Jaylen Brown, who feints a cut to the hoop to draw attention while the screening big man either sets up behind the arc (Horford) or rolls to the rim (Williams). Here’s what it looks like both ways:

However, Horford can’t get up like Williams, and Williams can’t shoot at all. Imagine running that with a big man who can do both!

Notice the quarterback in both instances: Marcus Smart. Smart was the best passer on the team, and the team will sorely miss his creativity. Tatum is constantly improving, but table-setting isn’t his role. Derrick White, Malcolm Brogdon (assuming he returns), and Payton Pritchard all can pass, but it’s not their respective strengths. Even with Porzingis’ spacing, the potential looms for the halfcourt offense to become a kludgy, mechanical mess, an old car engine leaking oil. Tatum, Brown, and Porzingis are too good for the offense to be bad, but the floor is middle-of-the-pack.

That said, it’s possible that allotting Smart’s minutes to more efficient and/or conservative scorers, such as Derrick White and Payton Pritchard, will offset the lack of passing spark. Vision is difficult to improve, but the driving and passing lanes should be even cleaner than last year, simplifying the reads for the ballhandlers. Porzingis will likely assume Smart’s shot volume (and then some!), and he’s a much better and more versatile scorer.

The Celtics were one of the worst offensive rebounding teams in the league last season, emphasizing five-out lineups and transition defense more than extra opportunities. While Porzingis isn’t an incredible offensive rebounder, having more size on the floor closer to the basket should still lead to more second-chance points.

Porzingis also averaged more than six free throws per game last season, which would have ranked second on the Celtics behind Tatum. Boston was 22nd in free throw rate last season, and the addition of KP should nudge that closer to the league average.

While I’m not sure where the offense levels out (although I think it’ll be quite good), perhaps more importantly, it will be more versatile. In the regular season, a team can get away with being great at just a couple of things, but in the playoffs, offenses have to have Plans B, C, and D. If Tatum has another of his strangely absent halves, or Jaylen Brown’s shot isn’t falling, coach Joe Mazzulla can call upon Porzingis’ three-level scoring and free throws.

While the team’s offensive orchestra has gained some instruments, they’ve lost two of their best percussionists on the other end. Smart and Grant Williams were Boston’s two most versatile defenders. Their absence locks Boston into more rigid schemes, which could compromise spring basketball defense.

This isn’t about Porzingis as an individual defender, where he was borderline All-Defensive Team last year. Teams shot both less frequently and less effectively at the rim when he was on the floor, per Cleaning the Glass, and he’s a little more nimble on the perimeter than ballhandlers expect. Porzingis thrives in drop defense, using his solar glider wings to stymie ballhandlers and rollers alike. Boston’s pick-and-roll defense last year with Horford was strong; KP’s addition could make it even better.

In fact, it wouldn’t shock me if the Celtics’ regular-season defensive rating improved from last year’s top-five mark (particularly if Rob can stay healthy for long stretches). Having three legitimately great big defenders will do wonders during the season’s grind, when opponents don’t have the time to craft bespoke offensive gameplans. In a vacuum, size is always a virtue.

But Smart was the team’s best screen navigator, even in a down defensive year. Part of the Celtics’ success was thanks to his ability to stay connected to star ballhandlers, and his absence may take some of the shine off the drop. Derrick White is an elite shot-blocker for a guard and might be a better overall defender than Smart, but he can’t stonewall bigs in the paint like Smart, either. And while Grant Williams may have been a tad overrated defensively, he was also the best non-Tatum option on big scoring wings like Jimmy Butler.

Those two could guard the positional spectrum. Now, the only player with any defensive versatility is Tatum, whom the team will likely try to shield from the most challenging assignments. After him, the best wing defender might be… the newly added Oshae Brissett? 

Grant Williams and Smart allowed the Celtics to switch and match up however and whenever they wanted, and with those two gone, it will be much harder for the C’s to do that. Flexibility is essential in the playoffs (we just saw New York bludgeon a stiff, brittle Cavaliers team that had no counterpunch), so the Celtics are in sore need of some yoga.

The playoffs are incredibly matchup-oriented. The best postseason defenses have several solutions to any problem. The Celtics lost two of their best answers.

A note on leadership: for as much as Marcus Smart meant to the Celtics emotionally, there have been enough eyebrow-raising quotes from the Jays and others to wonder if Smart’s constant chatter was grating on teammates. We’ve seen time and again in the NBA that sometimes situations grow stale, and voices get tuned out.

But Smart and Williams were the two most fiery and vocal players on Boston’s roster; someone will have to be a more vocal leader. Perhaps Tatum or Brown will be more comfortable assuming such a role with Smart in Memphis.

Boston came into this season with a plan. The Celtics wanted to add length without compromising their shooting, and they did it well. Unfortunately, plans are judged in hindsight. If the Celtics finally get their ring, it will look like genius maneuvering. If they struggle to replicate the deep playoff runs of the last few years, it will look like a desperate and misguided swing.

I don’t think they’re done making moves: if Brissett or rookie second-rounder Jordan Walsh can’t be the wing defender Boston needs, I have no doubt that they’ll try to find someone else to fill that role. Right now, though, the Porzingis for Williams/Smart swap increased the Celtics’ talent level while decreasing their pliability. We won’t know which trade-off matters more until the playoffs return.