With Joe Mazzulla out of sight and their starters watching in street clothes, the Celtics opened their preseason with a comfortable win Thursday night in Cleveland.
Led by big nights from third-string center Luka Garza, tryout guard Devin Carter and its slew of high-energy wings, Boston manhandled the Cavaliers on the offensive glass and cruised to a 124-113 win at Rocket Arena.
#### 1\. Coaching changeup
Mazzulla ceded head-coaching duties [to two of his longtime assistants](https://www.bostonherald.com/2026/10/08/celtics-announce-surprise-coaching-plan-ahead-of-preseason-opener/) Thursday night. Tony Dobbins, who has been in his role since 2020, coached the Celtics in the first half. DJ MacLeay (since 2022) took the reins for the second half. Dobbins and MacLeay also handled the pre- and postgame news conferences, respectively.
It wasn’t either’s first turn as a temporary bench boss — both have coached Boston’s Summer League team in the past, with Dobbins doing so in 2023 and MacLeay following suit in 2024 — and Mazzulla wanted to give them more experience in that role as they build their respective resumes. Dobbins and MacLeay both interviewed for head-coaching positions elsewhere this offseason.
The switch-up also allowed Mazzulla to view the game and his players through a different lens. He [told reporters](https://www.youtube.com/watch?v=MOIHCjZCCIs) at morning shootaround that he planned to watch “in the back with some of the guys who won’t play and the video guys that build the halftime edits.”
“Just really see what I don’t see when I’m out there (coaching),” he said. “So it’s just as much for me as it is (Dobbins and MacLeay). But I think it’s just seeing the game from a different perspective, and also giving those guys an opportunity.”
Another Celtics assistant, Sam Cassell, will coach the team’s fourth and final preseason game in Philadelphia on Oct. 16, per Mazzulla.
#### 2\. Starters sit
Like their head coach, most of the Celtics’ top players did not participate in this one.
Jayson Tatum, Paul George, Derrick White, Mitchell Robinson, Neemias Queta, Payton Pritchard, Sam Hauser and Ron Harper Jr. all got the night off as Boston took a longer look at its depth pieces. Seven of those players are established rotation veterans, with Harper the lone outlier. He’s dealing with a shoulder injury.
Mike Conley, Baylor Scheierman, Hugo Gonzalez, Jordan Walsh and Garza started for the C’s against a near-full-strength Cavaliers top unit (Donovan Mitchell, Peyton Watson, Evan Mobley and Jarrett Allen all played until halftime, with only James Harden missing).
Conley has started more than 1,100 games over his 19 years in the NBA, but he’s expected to play more of a reserve/leadership role this season when the Celtics are whole. The other four were impact role players on last season’s team who are battling for playing time in crowded position groups.
Draft picks Chris Cenac Jr. and Dillon Mitchell and tryout players Carter and Milos Uzan rounded out the rotation. Those nine more than held their own against a Cavs squad that reached the Eastern Conference finals this past spring, leading 32-29 after one quarter and 71-62 at halftime.
Boston took a 99-96 lead into the fourth quarter, at which point MacLeay emptied what was left of his limited bench.
#### 3\. Garza brings juice
The Celtics clearly weren’t satisfied with Garza as their No. 2 center last season. If they were, they wouldn’t have brought in the now-departed Nikola Vucevic at the trade deadline or signed Robinson this offseason.
But while Garza has his limitations, especially as a defender, he showed Thursday why he still can be a valuable piece in Boston’s fortified frontcourt. He led all scorers and helped drive the Celtics’ dominant offensive rebounding effort.
His final line: 22 points on 6-of-17 shooting, 10 rebounds (four offensive), two assists and three blocks in 27 minutes. Team-wide, the Celtics owned a 21-5 advantage on the offensive glass, including a 10-1 edge in the first quarter, despite not dressing several of their best rebounders.
Cenac, Boston’s 19-year-old rookie big man, also showed promise with six boards (three offensive), two blocks and some burst with the ball in his hands in his preseason NBA debut. The next step: dialing in his shot. The Houston product went just 3-of-13 and 0-of-3 from deep.
#### 4\. Impressive audition
No Celtic has more to prove this preseason than Carter, a 2024 lottery pick who had to settle for an Exhibit-10 training camp contract after being traded by Sacramento and waived by Atlanta.
This performance certainly will help his cause.
Boston’s coaches gave Carter plenty of run against Cleveland — he checked in midway through the first quarter and logged 19 minutes — and saw a plethora of positive moments from the former Providence College star. The 24-year-old scored 17 points on 5-of-9 shooting, went 6-for-6 from the foul line, added four rebounds and two steals, and finished as a game-best plus-22.
Carter also converted a pair of and-ones and assisted on 3-pointers by Garza and Gonzalez. He has to be viewed as the early favorite for Boston’s one open two-way contract slot, for which he is competing with Uzan, Tucker DeVries, Hayden Gray and Gabe McGlothan.
The Celtics, who also have one vacant 15-man roster spot, could benefit from introducing a young guard into their pipeline. Pritchard, White and Conley are 28, 32 and nearly 39 years old, respectively.
#### 5\. Wing report
Walsh spent the offseason working to expand his offensive game. So far, so good on that front. The fourth-year wing scored 16 points on 6-of-14 shooting while displaying a much deeper bag of offensive moves than he had in his first three seasons.
Scheierman had one frenetic first-quarter sequence in which he regathered his own blocked shot, fed a behind-the-back assist to Cenac, lost his shoe on defense, slipped it back on, immediately dove on a loose ball and flipped a pass to Gonzalez for a layup. He also went a team-best 4-for-7 from three.
Gonzalez finished with 15 points on 5-of-9 shooting and led the team with five assists, plus a slick one-handed entry pass that Garza couldn’t finish. His niftiest basket — a fast-break eurostep layup — came off a steal by Mitchell, who played with the same kind of disruptive energy he brought in Summer League (10 points, eight rebounds, four assists, two steals in 26 minutes).
#### 6\. Next up
The Celtics, who held three days of practice at The Citadel in Charleston, S.C., before flying to Cleveland, now return home for what could be an unusually compelling preseason matchup this weekend.
The Philadelphia 76ers will visit TD Garden on Saturday (8 p.m.) for what could be Jaylen Brown’s first appearance back on Causeway Street. It was unclear as of Thursday, however, whether the Sixers planned to play Brown in that game.
The former Celtics star started Philly’s first two exhibition games, dropping 22 points against the New York Knicks in his debut in blue.