Just how good has Daniel Theis been?

Brad Stevens’ experimentation with lineups has had some pretty clear cut consequences in the win-loss column. In a one-point loss to Sacramento, Grant Williams registered a DNP, prompting some questions about player rotations in Stevens’ post-game interview. I wrote about how this bothered me and how I didn’t like the reasoning behind sitting a player for an entire game as a way to find the team’s best lineups.

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In a close loss to Brooklyn, Daniel Theis played seven minutes in total, and none in the second half. Instead, Enes Kanter was called on, presumably to bully the smaller Jarrett Allen. I won’t go deep into this, so I’ll just say as politely as possible: it didn’t work.

I have been an ardent defender of the Brad Stevens legacy to this point. I’ve taken the noble duty of arguing with Twitter trolls when the infamous “Who would you rather have?” poll compared his influence to that of Giannis Antetokounmpo.

Yeah, I voted for Brad. What are you gonna do about it? Hold me accountable? This wasn’t a poll about basketball. It was a test of devotion. Make no mistake: I passed.

And while my faith hasn’t wavered since then, it has certainly been tested. This is the second time this season where one of the Celtics’ eight best (healthy) players have been benched in a close loss. So, I have to ask: Is it worth the consequence? Is it worth surrendering wins early to have somewhat of a better understanding of the roster later on?

Maybe we can frame the issue differently. Are we sure we know how good the team is already? Just how much of the early success can be attributed to each player? As Daniel Theis was the one to get the early hook on Friday, I figured it was time to give his contributions a closer look.

Some numbers would show that the Celtics aren’t strictly better with Theis on the floor.

Clearly, they’re a bit more efficient without him. At the same time, opponents are notably better against Boston when Theis goes to the bench.

Some of this can likely be attributed to how bad the team’s offense had been without Hayward. Boston’s “play ugly, win ugly” strategy hasn’t done well for anybody’s offensive numbers, even while the defense has held up. So while Boston struggles to score with some of their better lineups, so do their opponents.

Another note on Theis’ offense is the lack of three-point shooting. He’s taking about as many per game as usual (0.9), but has only connected on two of his 13 attempts. A 2-for-13 streak isn’t significant on it’s own, but compiled with the shooting (or lack thereof) of the other centers, it basically leaves Boston without any credible stretch bigs on offense except for... Marcus Smart?

Theis is taking 22.6% of his shots within three feet of the basket this year, compared to 12.8% last year, per Basketball Reference. His field goal percentage is down to 47.6% (from 54.9%) and his TS% is down to 52.7% (from 62.7%). There’s been a clear preference for the Celtics to score more in the paint this year than last.

While the offense has been flimsy with Theis (and basically anybody else), the defense has been steady. He’s blocking 6.6% of shots against him, which is eighth in the league. His 4.6 defensive box plus/minus is good for sixth in the league. It’s been easy for the more peripheral players to boost their stats while getting minutes with the team’s core pieces, but I don’t think that’s the case with Theis.

The defense is good in large part due to his rim protection, especially in contrast with Robert Williams and Enes Kanter, who struggle to read the pick-and-roll. Timelord’s defensive stats are still bananas, but that doesn’t mean he’s been consistent. Also, nobody dares to take floaters near him anymore. Theis, on the other hand, has been consistently good switching on smaller players and defending the rim. How many other Celtics bigs can do this?

I love that Theis doesn’t try to defend this by backpedaling with his arms up, but by sliding his feet and staying on Spencer Dinwiddie’s hip.

By the eye test--and the stats that back it up--Theis has proven himself as valuable to Boston’s rotation. Perhaps he was too dinged up or still feeling under the weather in Brooklyn, so we’ll call it a load management day and move on.

Seeing Theis do so well provokes more questions though: Why is Boston’s “weak” front court still such a topic of discussion? Why do I keep seeing trade suggestions for backups centers? Aren’t we past that now? Do we trust our eyeballs? Do we expect Theis (and Smart) to regress defensively? Call me a green teamer if you want, but I don’t see any pressure to make trades. When the Celtics are healthy, the offense will come back around, lessening the burden on Theis and other bench guys to score.