Lineup questions: who starts at center for the Boston Celtics?

With the exception of the perpetually-in-limbo 15th roster spot, the 2019-20 Boston Celtics are just about set in stone. What’s done is done: Kyrie Irving and Al Horford are gone, and in come Kemba Walker, Enes Kanter and a cadre of exciting rookies. It’s time for the Celtics to look forward and formulate exactly what this new iteration of the roster will look like.

I believe it’s safe to assume that Kemba Walker, Jayson Tatum and Gordon Hayward are all locks for the starting lineup. They’re the highest paid and highest upside players on the roster, and the three players most likely to earn All-Star honors this season. How things stack up around them, however, remains a little unclear. Let’s break down a few lineup decisions that Brad Stevens and co. will need to address in the early going.

Who wins the game of center roulette?

With Horford’s surprise departure to the Philadelphia 76ers, the Celtics find themselves entering the season without the All-Star center anchoring their starting lineup for the first time since 2015. There’s no way around this: the center position is going to take a dramatic step backwards without Horford (and Aron Baynes) in the fold, no matter what. With the right decisions, however, Stevens can at least mitigate the loss, and that will be crucial to this team’s overall ceiling.

Right now, the plan appears to be center-by-committee, with a four-headed hydra for Stevens to deploy: Enes Kanter, Daniel Theis, Robert Williams III and Vincent Poirier. None of the four have Horford’s versatility — there probably aren’t four other centers in the entire league who do — but for a coach who likes to play four-dimensional chess with matchups, the diverse combined skill set of the quartet should give him plenty to work with.

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Kanter is the strongest offensive option of the bunch, hyper-efficient in the paint and voracious on the offensive glass. Mutterings of a developing three-point shot could only improve his value. However, he’s almost certainly the weakest defender of the four, with lead feet and miserable defensive awareness. The Celtics will bleed points at the rim when he’s on the court.

Theis is likely the quickest of the group, and also Stevens’ most trusted; he’s a valuable rim-runner and team defender, with a nice ability to stretch the floor with his three-point shot. He’s traditionally struggled against larger defenders, however, and has committed 6.2 fouls per 36 minutes for his career. He may not be capable of staying on the floor for more than 20 minutes per night.

Poirier is perhaps the dark horse of the bunch, the latest in the Celtics’ string of EuroLeague acquisitions. He’s a lethal finisher in the pick-and-roll, which makes him an interesting fit alongside Walker and Smart, and he’s a decent passer to boot. He’s the kind of center who will blend in to just about any NBA offense right out of the gate. However, his defensive performance fails to inspire, as — much like Kanter — he may not have the quickness to survive off switches, limiting him to a strictly drop-defense role.

Then there’s Robert Williams, the Timelord himself. He may well be the most unknown quantity on the Celtics’ roster at this point in time. Williams scarcely saw the court last season, and the minutes he did receive were generally a mixed bag. At times, he was locking down All-NBA matchups like Anthony Davis, while at others, he looked overly eager to chase blocks at the cost of defensive positioning, making him a net negative on the court. There’s no doubt that he has the highest defensive ceiling of this group, but the question is whether he’s ready to reach it in just his second NBA season.

Smart money says Kanter will be the Celtics’ starting center on Opening Night, but as we’ve often seen with Stevens, it’s not about who starts as much as it is about who closes. Finding a reasonable distribution of minutes among the four centers will be crucial to realizing this team’s ceiling.