BOSTON, Mass. — Joe Mazzulla understands that things are going to look different this season.
There’s no Al Horford nor Luke Kornet, both of whom served as fixtures of his Celtics’ tenure. No Jrue Holiday nor Kristaps Porzingis, veteran voices of the Banner 18 team who were traded away in an offseason overhaul.
And Jayson Tatum, out for most, if not all, of the season as he recovers from an Achilles rupture, is sidelined (though in the building, tirelessly focused on his rehab).
But, despite the absences, the Auerbach Center — the Celtics’ home base and practice facility — doesn’t feel empty.
Training camp is teeming with an influx of younger talent, from Anfernee Simons — the Portland Trail Blazers’ leading scorer for the past two seasons — to more unproven players like Luka Garza and Josh Minott, who have shown plenty of promise in their early days. Longtime Toronto Raptors big man Chris Boucher and rookie Hugo Gonzalez round out the new additions.
“This is a different vibe of training camp with a lot younger guys than before, so we got after it,” said Xavier Tillman, who is entering his third season with the Celtics. “[We’re] running around a lot, coaches screaming, you’re kind of just turning your head getting to the next spot. But it was fun. It was good.”
Sam Cassell, the Celtics’ top assistant coach, said on 98.5 Sports Hub that he’s never seen a training camp quite like this one.
“I’ve been in this business 34 years,” Cassell said. “And this is the hardest training camp [I’ve seen] right now.”
With so much talent out the door, the Celtics recognize the importance of being the hardest-playing, most connected team. That process started 12 weeks ago.
Camp is the culmination of a summer of tireless work
This summer, most Celtics players have been in the building for months. That wasn’t the case last offseason, when the team was fresh off a championship and three players played for the Olympic basketball team.
Tatum and Brown both rehabbed their respective offseason surgeries in Boston. Payton Pritchard spent some time in Cape Cod, Spain, and Oregon, but he’s been working out daily in the Auerbach Center since August.
Derrick White was in Colorado for much of the offseason, but returned last month as well. Neemias Queta was in Portugal — and then Latvia, for EuroBasket — but shot back to Beantown upon the tournament’s conclusion.
And, the younger guys — Baylor Scheierman, Jordan Walsh, Hugo Gonzalez — have since become fixtures of the facility since Summer League concluded in Las Vegas.
“We’ve been here all summer,” Scheierman said, explaining that workouts have brought everyone closer. “All of the guys really have become super comfortable with what the coaches are preaching to us.”
As such, new duos and social dynamics are forming. For example, Xavier Tillman and Luka Garza — once college rivals playing for Michigan State and Iowa, respectively — typically shoot together for 20 to 40 minutes a day.
“Sam [Hauser] calls us the buffaloes,” Tillman said with a smile, explaining he got up a “tireless” amount of three-point shots in the summer after a disappointing 2024-25 season.
Players have been honing in on individual weaknesses ahead of a season where the margin of error will be noticeably thinner. For weeks now, Anfernee Simons has been methodically working on defensive playmaking drills focused on getting in passing lanes, improving defensive positioning, and racking up deflections.
“Those things are things I never really worked on or been taught,” Simons said. “And so I was happy that that was the focus.”
Still, as intense as summer workouts have been to date, things reached another level when camp officially tipped off on Monday.
For one, it’s the first time that the entire roster is present, all at once. And, the intensity and pace immediately picks up. There’s also the collective understanding that real games are inching closer; the Celtics’ preseason officially tips off next Wednesday in Memphis.
“You should have a foundation based on what you’ve been able to do,” Mazzulla said. “So, you’re able to move at a faster pace, you’re able to teach a little bit more. But, really it’s just the intensity and the mindset — this is preseason training camp.”
In the background, Exhibit 10 and two-way players anchor camp
Alongside the 14 Celtics players who are on standard contracts (five of them brand-new), three training camp attendees are on two-way contracts and four are on training camp (Exhibit 10) deals. The Exhibit 10 players — Kendall Brown, Jalen Bridges, Wendell Moore, and Ron Harper Jr. — are fighting for a more certain NBA opportunity and will join the Maine Celtics at the conclusion of camp. (Brown and Bridges also played on the Celtics’ Summer League team in July).
The two-way players — Max Shulga, Amari Williams, and RJ Luis — are also likely to spend most of the season in Maine. In the meantime, they’re deepening their relationship with Phil Pressey, the first-time head coach of the Celtics’ G-League affiliate, who is at training camp every day.
That means that exactly one–third of training camp participants arrive with the understanding that their days with the parent club are numbered. But, for the weeks that they’re with the team for preseason, they’re just as much a part of the program as anyone else; for example, at the Celtics’ opening day spikeball tournament, Derrick White was paired up with training camp returnee Ron Harper Jr., as the team captured on TikTok. (It’s Harper Jr’s second consecutive year attending Celtics training camp).
At camp, Mazzulla expects the non-rostered players to learn the system and push one another the same as the more high-profile guys on the team.
“It’s the same standard as everyone else,” he said. “Any way they can help us get better — they do that.”
“Everyone’s got to know what they do really matters, and whether it’s the first guy or the 15th guy. If they don’t feel like they’re empowered, [that] they can impact winning, then we just can’t have the balance, and the depth, and the culture that we need.”
Joe Mazzulla, Jaylen Brown prioritize off-court connections
As he leads training camp, Mazzulla rejects being called ‘coach’ by his players.
“I can’t even explain the relationship,” Simons said. “It’s, like, almost as a mentor.”
That translates to an expedited level of buy-in, Simons explained: “It makes you want to go out there and play for him even more when you have that connection off the court. And he’s really invested in the off-court life.”
Simons said Mazzulla often asks about everyone’s kids. He’s dropped things off at Simons’ new home, making sure that his acclimation to Boston is smooth. He’s learning what makes the new guys tick.
“He takes a lot of time to personalize his relationships with people,” Josh Minott said. “He doesn’t talk to any two people the same way.”
Last month, Mazzulla and several members of the coaching staff attended Chris Boucher’s baptism, a gesture that made the 32-year-old feel like he was officially a part of the “brotherhood.”
“It’s not easy to move and start over again,” Boucher said of his relocation from Toronto. “But Joe really helped me with that. Brad, too. It’s been a really, really, really warm welcome.”
And as such, in separate interviews, both Garza and Minott — former Minnesota Timberwolves teammates — have offered that they’d “run through a brick wall” for Mazzulla.
“He just has that effect on people,” Minott said.
“Every time he says something, it’s incredibly impactful,” Garza said.
But, it’s not just the Celtics’ head coach who recognizes the importance of cultivating deep off-court bonds.
Jaylen Brown, the team’s most veteran player, has made a concerted effort to bring players together off the court — whether that’s by facilitating team bonding events (a portion of the team together attended an NBA YoungBoy concert on Sunday) or by having players over at his home.
“JB has always been a leader for us,” Scheierman said.
“We’ve got a whole new team, and people think that all the pieces are supposed to fit together,” Brown said on NBC Sports Boston on Monday. “It doesn’t work like that.”
Last year at training camp, there were few new faces, with the entire Banner 18 roster, save for Svi Mykhailiuk and Oshae Brissett, returning for another shot at a title. This year, that’s not the case.
“We’ve got to make up for lost time to make sure that the product when we get to the first game of the season is there,” Brown said. “We got to spend some more time with each other and really try to chemistry-build as much as possible, from now until the end of the season. It takes work.”
Brown and six of his new Celtics teammates attended a Patriots game last weekend.
“[It’s] dinners, concerts, events, inviting guys to the crib, the house — all that type of stuff,” Brown said.
The Auerbach Center feels different. The absence of Horford, Holiday, and other veteran voices means that new guys are finding their voices and unique leadership styles.
At the same time, despite the losses, there’s an undeniable sense of energy and connection surrounding camp. With Opening Night just a few weeks away, there’s plenty of new schemes and terminology for everyone to learn.
But, the laughter, personal connections, and team bondings matter too.
“We’re trying to build a family with the new guys,” Jordan Walsh said. “That’s important.”
