Coach Joe Mazzulla, Marcus Smart and the Celtics continue seeking ways to push for a return trip to the Finals.

The dog days seemed to swoop in as swiftly as the frigid weather, leaving the sting of Boston’s second three-game losing streak of 2022-23 even more biting ahead of the All-Star break.

Knock, knock, knock.

That thud echoed through the silence of pregame media availability as Celtics interim coach Joe Mazzulla tapped a table to dispel the mere mention of another skid that would soon be extended that night courtesy of the visiting New York Knicks.

“Great teams know why they’re good, and why they’re good all the time,” Mazzulla said later, eyes darting around the room after Boston’s 120-117 loss in overtime on Jan. 26. “So, we just can’t take possessions or time in the game for granted. I didn’t think we played consistently the entire game — physical, detailed, connected basketball. When we turned it on, we really did. We just have to do that all the time.”

Sounds simple enough, right? Especially for this young-but-battle-tested Celtics squad that boasts a starting 5 with a combined 430 postseason appearances, with multiple showings in the Eastern Conference finals culminating in a 2022 NBA Finals berth. Yet it is here, in these cold, dark days heading into the All-Star break, where Boston’s young veterans hunker down and focus on developing the habits required to push the Celtics past the disappointment of their loss to Golden State in last year’s championship round.

“Just not getting bored with the simple plays, just doing the little things that work all the time,” Mazzulla explained. “Sometimes that can be really hard over the course of a long season, and you just can’t get bored with doing those things. They are very, very simple, and the simplest things breed the most rewards on both ends. Being a great team is really, really hard. You just have to work at it every single day, and you’ve got to do the small, boring things all the time.”

Yet with 7.6 ticks left in OT and the Celtics trailing by one against the Knicks that night, Jaylen Brown missed two crucial free throws — “smoked it,” he said — which immediately forced the home team to foul.

Game over.

Brown would suffer a facial fracture 13 days later in a win over Philadelphia that will keep him out of action indefinitely, but on this cold January night he admitted that “yeah, at times,” Boston can become bored with the small details.

Brown admitted that Mazzulla’s critique was “at times” correct.

Star forward Jayson Tatum added, “I think human nature plays a part.”

Despite their league-best record, maintaining proper focus to perform simple tasks repeatedly throughout the rigors of an entire game remains an elusive objective for the Celtics. But multiple current coaches around the league said such issues affect most teams, which is why true title contenders are so few every season.

“That’s a part of the season and also reflects leadership,” Brown said. “As one of the leaders I’ve got to do better making sure my energy is contagious to the rest of our group. Tonight was an example. I dropped the ball as a leader. Those two free throws at the end kind of just embodied that whole performance tonight.”

‘A lot of sad guys’

Jayson Tatum and the Celtics didn’t finish their 2022 Finals run as hoped.

Boston learned a similar lesson the hard way last season, falling 4-2 in the Finals to a seasoned Warriors squad that gorged on careless Celtics turnovers. In the final three losses of that series, Brown and Tatum combined for 22 giveaways.

Throughout the 2022 playoffs, Boston was 13-2 when it committed 15 turnovers or fewer and 1-8 when it had 16 or more. The Celtics averaged 19 turnovers in the Finals, which the Warriors converted into 23.5 points per game as they rallied from 1-0 and 2-1 deficits. Conversely, Golden State surrendered more than 23 points off turnovers only once in the series.

In the decisive Game 6 at TD Garden, Boston sprinted to a 14-2 lead, only for the visitors to answer with a 35-8 run to seize a lead they would never relinquish on the way to winning the franchise’s fourth title in eight seasons.

Crushed in the postgame locker room, the Celtics quietly pondered what could have been as the Warriors celebrated on their home floor. Boston was proud of its effort, how the banged-up squad battled through two seven-game series vs. East heavyweights to arrive at this disappointing conclusion. It marked the end of an emotional roller coaster for the Celtics after they rebounded from a 25-25 start under first-year coach Ime Udoka to embark on their Finals run that fell short due to the turnovers and a magical Game 4 performance from Stephen Curry.

In fact, there was a belief among some within the organization that if Curry misfired on one or two of the seven 3-pointers he drained in Game 4, Boston might have taken a 3-1 series lead to increase its prospects of winning the franchise’s second title since 1986.

“It was a lot of sad guys in that locker room,” said Celtics guard Derrick White, who joined the team last February through a trade with the San Antonio Spurs. “It was quiet.

“Being so close, man, just two games away from the ultimate goal of a championship, everyone was kind of dealing with it in their own way. I just kind of looked back on all the games and tried to find those little things you could’ve done different or better. Just to be so close to it and not get the job done, it hurt for sure.”

Boston emerged from the aftermath determined to make consistent execution for an entire 48 minutes a major emphasis for 2022-23.

Growing up together in playoffs

Jayson Tatum (center), Jaylen Brown (left) and Al Horford finally achieved East supremacy in 2022.

Tatum entered the league in 2017 at 19 on a team already featuring Brown, Al Horford and Marcus Smart, and the Celtics went 55-27 to finish No. 2 in the East, defeating Milwaukee and Philadelphia in the first two rounds of the playoffs before losing in Game 7 to the LeBron James-led Cleveland Cavaliers.

“That was my first year in the league,” Tatum said. “So, just to go deep in the playoffs like that and go to Game 7, we were battle-tested. Gaining that experience in my first year really helped me out. It helped our team out a lot.”

Playing for Brad Stevens, who is now the team’s president of basketball operations, Tatum would participate in two more Eastern Conference finals, while Smart and Brown played in three apiece. Horford saw two East finals berths with Stevens before the foursome finally reached the Finals under Udoka.

“Early on, being able to be thrown into high, intense moments with everybody watching against some of the best players in the world kind of led to cultivating the experiences that we get to see now, the growth, the basketball maturity, how to win games,” Brown said. “All of that comes into play.”

Of the 12 players leading the Celtics in minutes, just one (Sam Hauser) has participated in fewer than 11 playoff games, while only one more (Blake Griffin, with 67 games of postseason experience) hasn’t played beyond the conference semifinals.

So, when Mazzulla stresses the importance of mental toughness, his players understand intimately, having seen it up close so many times over the years through victory and defeat.

“We’ve been in big moments,” Tatum said. “We succeeded a lot of times in big moments, and we’ve come up short. But we’ve been able to learn from and take something from each playoff series, each time we went, conference finals three or four times and the Finals last year. So, we’ve been in a number of big games. I think just gaining that early experience can only help you in the present time now and for the future.”

What about now?

Celtics interim coach Joe Mazzula has put his own unique stamp on the team.

Boston’s recent three-game losing streak represents a mere blip on the radar of adversity navigated thus far with an eye towards drawing strength from the tough times. The Udoka suspension dominated the headlines in September, confusing the players and reshuffling a coaching staff that three months earlier had already lost top assistant Will Hardy to the Utah Jazz.

Mazzulla stepped into the role as interim coach (he’ll also coach Team Giannis at the NBA All-Star Game), and the Celtics never missed a beat.

Described by colleagues as serious, detailed, hard-charging and driven by faith while possessing unbreakable bonds with the players, Mazzulla calmed the turmoil and uncertainty in the locker room and guided the Celtics to a 20-5 start. By the start of 2023, Mazzulla was returning from a two-game absence due to corneal abrasions suffered in a competitive pickup game ahead of Boston’s Dec. 27 win over the Houston Rockets.

That’s right, Mazzulla competes in pickup games at TD Garden (and doesn’t plan to stop despite the injury) approximately four hours before home games. In those settings, you can catch a glimpse of the competitive fire burning inside the interim coach.

“He’s similar [to Udoka],” White said. “Joe was a part of Ime’s coaching staff, so he knew what we were doing and everything else going on. Each coach is a little different with the way they speak and everything, but the concepts are all pretty much the same.”

After a 25-25 start in 2021-22, the Celtics achieved a mark of 35-15 over the first 50 games of this season that concluded with the club’s second three-game losing streak. It started in Orlando after Boston had captured nine consecutive victories, followed by a 98-95 loss at Miami. Next, the Knicks edged the Celtics in OT on the strength of Julius Randle’s game-high 37 point and the late missed free throws by Brown.

The postgame conversation between Mazzulla and Brown that night was simple.

“I love you Jaylen,” the coach said. “And I believe in you.”

Tatum joked afterward: “I can’t bet on NBA games, but I would bet everything I’ve got if he’s in that situation again, he would knock them both down.”

Interestingly, two nights later, with James and the Los Angeles Lakers in town, Brown stared down a scenario similar to the one that sunk Boston against the Knicks.

The Celtics trailed 105-104 with 4.1 seconds left in regulation, and Brown calmly stepped to the line to hit the free throw that would send the game into overtime. The 26-year old played the last 12 minutes of that contest with five fouls and poured in 20 of his team-high 37 points during that span, including 11 in the extra period.

Losing skid snapped, Boston wins 125-121, and the Celtics move on to log victories in four of their next five matchups.

“Resiliency is a key to trying to build a great team,” Brown said. “It’s funny how life works, just one game later. I knew I would get that opportunity again, but I didn’t know it was going to be the very next game. You step up to the line, trust yourself and do what you’ve got to do. You don’t let one game define you. You don’t let one moment define you. You learn to appreciate those moments because they spark something in you to be more focused, more locked in, and you have to trust and believe yourself even more.”

It’s a mentality Boston dreams of carrying into June of 2023.

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Michael C. Wright is a senior writer for NBA.com. You can e-mail him here, find his archive here and follow him on Twitter.

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