BOSTON — What made the Boston Celtics’ embarrassing loss on Tuesday so jarring was just how out of character it was for this team.
One of the hallmarks of this year’s squad has been an ability to catch itself when things go sideways. To get a clutch stop when it’s needed most. To avoid the boneheaded foul in an unforgivable spot.
Last year’s Celtics, which many C's fans remain scarred from, made these sort of disasters a routine occurrence. How ironic, then, that fans inside TD Garden were mockingly chanting, “Where’s Kyrie?” as the Celtics fumbled away a 21-point lead, let Caris LeVert and the Nets hang an absurd 51 fourth-quarter points, and watched Marcus Smart commit an impossibly bad foul with 0.2 seconds left that forced an overtime the Celtics were ill-equipped to survive.
It was a complete and utter meltdown by both coach and players. One that could have been swept under the rug if Smart doesn’t smack LeVert’s arm with big men Daniel Theis and Robert Williams already enveloping him on the final gasp of regulation. Barring a prayer, Boston would have escaped with an ugly win and turned its attention to the second night of a back-to-back in Cleveland.
Instead, we’re left to wonder not how it all fell apart, but how the team responds to its first true disaster of the season, all with a new rash of health woes.
Smart, the veteran this team is supposed to be able to lean on, compounded his end-of-regulation mistake by fouling out early in overtime on another facepalm-worthy infraction when he steamrolled into a defender for an offensive foul.
With Gordon Hayward (knee bruise in first half) and Jaylen Brown (hamstring strain in fourth quarter) sidelined, Jayson Tatum sick, and Kemba Walker having reached his minute limit as he returned from a five-game absence, it left Stevens employing an extra-session lineup of Brad Wanamaker, Carsen Edwards, Javonte Green, Semi Ojeleye, and Daniel Theis.
LeVert scored eight consecutive points to start the extra session, scored all 11 of his team’s points overall to cap his 51-point night, and the Nets emerged with a 129-120 victory. A calm-but-fuming Stevens scolded himself and his team. And he seemed to call out Smart for not being more aware in the late-game situation.
"We made a lot of plays today that were just not winning plays,” said Stevens, using a familiar bit of the Smart lexicon.
The coach is not absolved here. There were questionable decisions about the rotation, including the number of bodies trotted out early, and the decisions on who to lean on as availability thinned.
Smart, though, ratcheted things from bad to worse to disastrous when he confronted the three game officials near midcourt after the final buzzer. An initially peaceful confab deteriorated quickly with Smart pointing angrily in the direction of official John Goble, who had whistled Smart for an end-of-regulation foul that replays suggested he deserved and cursing at him while protesting the game-changing call.
Team and arena security eventually muscled Smart away from the officials and back to the locker room but it seems inevitable that he will be fined, and likely suspended, for his outburst.
Unless Tatum recovers from his illness, Boston’s available bodies in Cleveland could consist of only one typical starter (Theis), one established veteran (Enes Kanter), and a bunch of role players (Ojeleye, Wanamaker, Green, Robert Williams, Grant Williams, Edwards, Semi Ojeleye, Romeo Langford, Vincent Poirier, and, potentially, two-way G-Leaguers Tremont Waters and/or Tacko Fall).
“I have no idea who’s going to Cleveland,” said Stevens. "I think most of the coaches are going. I just want eight guys, nine guys, whoever’s going to play hard, let’s go. Like, that was ridiculous.”
Stevens admitted he could have subbed some of his rotation guys earlier when the lead started to evaporate but lamented how his team allowed momentum to snowball and then overwhelm them.
“Teams of runs lose. Teams that can stay in the moment and play the next possession the right way and not be influenced by the score, not be influenced by the situation of the game, the circumstances of the game, or have a different level of toughness and special toughness,” said Stevens. "We’ve exhibited that most of the year. I think that this is an anomaly but, nonetheless, it was a very humbling one. But that was ridiculous.”
Inside a hushed Celtics locker room, players struggled to grasp how it all fell apart.
"You have to treat it as a learning experience and that, when you take your foot off the gas pedal, they can come back on you,” said Hayward. "You just have to be better on both ends of the court. I thought we did a really good job building the lead but, certainly, they stormed back and then tough plays at the end for us.
“You're around this league a long enough time, 20, sometimes 30 points isn't enough. Like I said, as soon as you take your foot off the gas pedal, guys get hot, short possessions, and there's always time to come back. We just have to be better. Tough losses.”
Walker dubbed it the “toughest [loss] of the year.” It’s hard to think of one that’s even close.
Boston has had tough nights, including an overtime loss against the Rockets over the weekend. But these Celtics have almost always put up a fight, even charging back from a big deficit after falling behind big in Milwaukee in mid-January.
But the Celtics came completely unglued on Tuesday. Now, we find out how they put themselves back together.
How does Boston respond? Does this team do what it’s done in small pockets of adversity this season and steady itself after a bit of turbulence? Or will Tuesday’s loss threaten the foundation of it all?
“We blew it,” said Stevens. "That happens in sports sometimes.”
For these Celtics, it hadn’t happened this season. Now, they’ve got to prove it was an anomaly.
Don't miss NBC Sports Boston's coverage of Celtics-Cavaliers, which begins Wednesday at 6:30 p.m. with Celtics Pregame Live, followed by tip-off at 7 p.m. You can also stream on the MyTeams App.