Joe Mazzulla and the Celtics have created a relentless culture of winning

Regardless of who has been on the floor, the defending champions have fittingly been the best team this preseason.

BOSTON – Every now and then, confetti still falls from the rafters at TD Garden. In a Saturday night Celtics thrashing, a small piece of paper landed on Derrick White’s head. On Sunday, a few pieces were collected by an excited courtside fan who immediately handed them to a young boy sitting a few rows back.

The sporadically falling confetti serves as a reminder that the Celtics are less than four months removed from a postseason run that saw them go 16-3 en route to an 18th championship. It’s a fitting sight: a Payton Pritchard-led Celtics team leads by 40, and the falling celebratory tokens accentuate the lopsided scoreboard.

A night after the Celtics blew out the 76ers by 50, they ran the Toronto Raptors out of the building, too (with the exception of a fourth quarter that featured few players likely to make either teams’ roster). The pair of resounding home wins came just a week after two preseason victories against the Denver Nuggets in Abu Dhabi.

The preseason dominance demonstrates a sentiment that Joe Mazzulla and the rest of the Celtics have expressed since training camp began: last year’s championship is last year’s, and there will be no championship hangover in Boston this season.

So far, that’s been the case regardless of who has been on the floor. On Sunday, a lineup featuring Jordan Walsh, Lonnie Walker IV, Sam Hauser, Payton Pritchard and Neemias Queta jumped out to a 20-point first quarter lead against the Raptors, who had two regular season starters out there in Scottie Barnes (an All-Star) and Jakob Poeltl.

Jordan Walsh, who spent most of last season in the G-League, capitalized on his preseason start, posting 16 points and 10 rebounds. While most of the Celtics’ rotation players were out — Jaylen Brown, Jayson Tatum, Al Horford, Kristaps Porzingis, Jrue Holiday, Derrick White, Luke Kornet, and Xavier Tillman were all unavailable — the Celtics still locked down defensively to ensure the win.

“We know what the standard is, being here,” Walsh told reporters after the game. “We know what the responsibility of being a Celtic is — playing defense.”

It all starts with Joe Mazzulla and the coach staff, a young, analytically-driven group who have together created an offensive and defensive system that breeds winning.

Mazzulla Ball, as it’s become colloquially known, is a three-point-heavy offense that centers on making easy reads, creating two-on-one advantages, and emphasizing the undeniable connection between defense and offense. The principles are relatively simple, but the schemes are complex, and the correct read is the result of a whole lot of number-crunching that players have learned to incorporate into their decision-making.

Last year, the Celtics used Mazzulla Ball to outscore opponents by 10.7 points per game — the fifth-best point differential in NBA history. They also ran the most efficient offense in NBA history, scoring 122.2 points per 100 possessions, and posted the second-best defense in the league.

In the national media, a lot of the winning was attributed to the sheer talent on the roster — and there was certainly no shortage of that — but an underrated part of last year’s success was that the team rarely missed a beat in the absence of key players.

In the 2023-24 season, the Celtics went 21-4 without Kristaps Porzingis, 7-1 without Jayson Tatum, and 12-0 without Jaylen Brown. And, it was two Celtics bench players, not stars, who held the best net ratings in the league last season. Sam Hauser (+14.2), Payton Pritchard (+13.6), Derrick White (+12.5), and Luke Kornet (+12.1) rounded out the top-four individual ratings.

So far this preseason, the Celtics are outscoring opponents by 20.5 points per game, while no other team has a net rating of more than +8.9. Through four games, they have the league’s highest offensive rating. Payton Pritchard again boasts the second-best net rating in the league, at +17.8 in four games played.

Preseason results don’t really matter, but the Celtics’ dominance is indicative of a larger trend: that Joe Mazzulla and his staff have created a culture of winning that, so far, has withstood substitution patterns and injuries.

Pritchard has perfectly embodied the balance between pursuing individual greatness — he’s made it clear that that’s what he believes he’s capable of — while still playing within the Celtics system and thriving in his role as the backup point guard.

“I have big dreams for myself, and people want to put limits, and I put no limits on myself,” Pritchard said. “But I also have an understanding of what’s in front of me — we have a tremendous team that could win another championship.”

“At the end of the day, I’m a winner and I want to do whatever it takes to help the team win. I’m not going to sit out here and say ‘oh, I deserve more.’ We just won a championship, and I want to go and do my role the best I can. But, if there’s an injury or anything, I want to be able to step up in those moments and help the team.”

There’s been an undeniable level of focus, an unapologetic mindset, that’s permeated the starters who have played this preseason. Jaylen Brown began his preseason home debut by making a “too small” gesture after scoring on 76ers undrafted rookie Justin Edwards.

Brown, fresh off a Finals MVP and what he’s deemed the best summer of his life, racked up 18 points (7-12 FG), 8 rebounds, and 4 assists in 23 minutes on Saturday.

The Celtics starters were facing a bunch of end-of-bench players, but, for better or worse, they didn’t act like it for a minute.

“It’s about us. So, every time we step out on the floor, it doesn’t really matter who the opponent is,” Brown said after the win over the 76ers. “We just gotta play our standard of basketball. That’s the tone that we set throughout training camp, and that’s the mindset that we have.”

It’s still early, but the Celtics have also appeared to have avoided the infamous championship hangover. While Nuggets coach Michael Malone lamented his team’s poor conditioning after three consecutive preseason losses, Mazzulla has routinely praised what he’s seen across the board at training camp. There is no talk of a title defense; instead, the team is on the attack.

“The phrase ‘defending a title’ is a very passive-aggressive term,” Mazzulla famously said on the Locked on Celtics podcast this summer. “If you look at the animal kingdom, some of the strongest animals don’t defend; they’re the most aggressive, and they attack the most. Whether you’ve won or haven’t won, your mindset can’t change. You have to understand what goes into winning and losing, commit to the details on a daily basis, and remain aggressive. You’re not defending something, you’re attacking a new goal.”

Likening a championship pursuit to the animal kingdom might sound strange at first sight, but the Celtics are both used to and bought into unorthodox comparisons and perspectives from Mazzulla. And, they’re happy to participate in a grueling training camp in preparation of another chance at a title run.

“Joe Mazzulla is a psycho in a good way,” Jaylen Brown said last month. “It’s probably one of the tougher training camps I’ve had in terms of intensity conditioning, physicality, and defensive warrior-type mentality.”

Jrue Holiday joked that the early days of camp have been so difficult, he wished he could have missed them as he did last season.

“I was traded last year, and I think I missed the first day,” said Holiday. “I wish I missed the first day this year, too.”

The reality is that no NBA team has won back-to-back titles since the Kevin Durant Warriors did it in 2017. In fact, no defending champion — sorry, Joe — has even made it past the second round since then.

The Celtics have a long road to go — they haven’t even raised the 18th banner — but through a month of training camp and preseason dominance, it’s obvious that their 36-year-old coach has created a system that gives them as good a chance as anyone — no matter who is playing, or who they’re playing against.