The Boston Celtics will likely manage just fine without Nikola Vucevic, as Luka Garza alone is enough to fill the void until he returns. However, with him for maybe the rest of the regular season, the Celtics may be on the prowl for another big man simply for depth purposes.
There isn't exactly much to choose from as the best available big men don't scream "solid dpeth signing."
That includes Chris Boucher (never fit in Boston, and they can't re-sign him anyway), Mo Bamba (Jazz might keep him once his 10-day contract expires, Tony Bradley (he was *technically* on last year's Pacers team), and Dario Saric (as washed as washed gets).
So, yeah, not looking too great. However, Stevens has shown in the past that he likes bringing back players Boston has worked with before. Since taking over as GM, he's brought back Al Horford, Enes Freedom, and Dalano Banton.
With the Celtics now down a big, he could exert that again by bringing back Daniel Theis.
Theis would be perfect as an emergency big man signing
Theis last played in the NBA last year before continuing his professional basketball career overseas. His numbers with the New Orleans Pelicans are far from spectacular, but they are still good enough for a team like Boston to talk itself into bringing him in - 4.3 points, 4.3 rebounds, 0.5 blocks, 47.3% shooting from the field in 16.3 minutes a game.
As far as player who would come in primarily as an emergency big, Boston could do much worse. Plus, for sentimental reasons, Celtics fans would love to see Theis back wearing green.
Theis became a fan favorite during his time with the Celtics, primarily because he was a surprise contributor when no one expected it. From there, he rose to become Boston's starting center, who went to the Eastern Conference Finals in 2020.
Like Danny Ainge, Brad Stevens has never been one to let sentiment affect his decisions, but with Vucevic out indefinitely, Theis would be brought back not just because he was well-liked, but because he'd be nice to have behind Neemias Queta, Luka Garza, and Amari Williams.
The Jays wanted Theis back before
Boston orchestrated a Theis reunion four years ago, but the reunion didn't last long, as Theis was then traded to Indiana in the package for Malcolm Brogdon.
However, his time with the Pacers didn't last long, as they waived him a year after acquiring him, paving the way for a potential return to the Celtics. Theis joined the Clippers, but it was confirmed afterward that Jayson Tatum and Jaylen Brown reached out to him after he cleared waivers.
Now that there's somewhat of a need in the frontcourt, nothing should stop them from trying again!