The 2025 Playoffs were an eye-opener for the Boston Celtics. Specially for head coach Joe Mazzulla. Yes, sure, he’s the no-nonsense kind. The one who knows what he wants the team to do. Yet when Jayson Tatum fell on the floor with a snap in his ACL, the Cs crashed. Severely. And despite having an edge over the New York Knicks, given their championship-winning season in 2024, Mazzulla and Co. could do nothing. And sometimes, you wonder why…

The Knicks stormed through Boston with a flair that felt impossible yet undeniable. They won the series 4–2, averaging 105.7 points against the Celtics’ 105.2, with 46 rebounds, 20.2 assists, and 6.8 steals per game. Boston had 43.8 rebounds, 19.8 assists, and 5.7 steals, plus 5.8 blocks. But the numbers never rescued them. Two 20-point blown leads at home set the tone, and history leaned New York’s way.

Game by game, the wildness only grew. Game 1 saw Boston go 15-for-60 from deep, setting a playoff record for futility. Jalen Brunson and OG Anunoby each dropped 29 in that shocker. Game 2 ended 91–90 with Brunson’s clutch free throws. Boston fought back in Game 3 with a 115–93 punch, but Brunson’s 39 and 12 assists in Game 4, plus Tatum’s injury, shifted everything. By Game 6, the Knicks sealed it 119–81. So now, as the Cs move ahead into the 2025-26 season, the 2024 championship-winning core feels shaken. The Celtics sent away Jrue Holiday and Kristaps Porzingis, and Jayson Tatum might miss this upcoming season.

Meanwhile, Dan Shaughnessy torched Boston’s flameout with a sharp edge on SiriusXM. Losing to the Knicks stung, especially after coughing up two 20-point cushions at home. He called it impossible, a collapse laced with stubborn overreliance on threes. Fans, particularly the old guard, saw the obsession as the Celtics’ undoing. “Joe’s very stubborn. They stayed with it. Maybe that changes when you take Tatum out of the Knicks this year, and Holiday is out of the Knicks. Even Porzingis, they all like jacking him up now,” the veteran writer said.

“They took more and made more than any team in history last year, but it sunk them in the end. And as you say, you’re totally correct. Stevens loves him, as Danny Ainge loved him. He just got the contract extension, so he’s here. And I think Tatum likes him, but Tatum is not going to be around very much this year. So we’ll see where it goes, but he’s a little bit behind the eight ball, even with the new deal,” Shaughnessy concluded.

The Celtics locked in Joe Mazzulla. Boston handed him a multi-year contract extension, a move that cements his role for several more seasons. The Celtics kept the financial terms sealed, but the message rang loud. Amid departures and shifting rosters, their head coach remains the constant, the man entrusted to steady the green ship once again.

His rise carried drama. In September 2022, he stepped in for a suspended Ime Udoka just days before camp. Three seasons later, the Rhode Island native owns a 182–64 record, a sparkling .740 winning percentage, and the 2024 championship banner. Those numbers built the trust. Those numbers made the extension inevitable, turning Mazzulla into Boston’s enduring pillar.

Yet, with Jayson Tatum‘s absence from the team, Mazzulla needs to find a new anchor who can hold down the Cs in such peril. Jaylen Brown is there, but he needs the support on the floor. Who?

The Celtics shake hands with Ron Harper Jr. amidst Jayson Tatum’s absence

The Boston Celtics reached into their bag of moves and pulled out Ron Harper Jr. on a likely one-year, non-guaranteed deal, per Michael Scotto. The 25-year-old last played under the Pistons’ banner before being waived from a two-way contract on July 24. Before that, he built his path through Rutgers, going undrafted in 2022, yet never straying from the grind.

His pro story keeps finding new pages. Harper logged most of his minutes in the G League, stacking 16.2 points, 3.9 rebounds, and 2.2 assists over 37 games with the Motor City Cruise and Maine Celtics. He launched threes at a furious pace, hitting 38.6 percent on more than eight attempts a night. His roots run deep, too, as the son of Ron Harper and older brother of No. 2 pick Dylan Harper.

The storm has already passed, but the echoes still rattle Boston. The 2025 Playoffs stripped the shine, Tatum’s ACL snapped the rhythm, and two 20-point collapses gave New York the stage. Joe Mazzulla stays, numbers backing his extension, yet faces his steepest climb. With Harper Jr. arriving and Brown searching for support, the Celtics now stand on a cliff, waiting to leap or crumble.