BOSTON — The Boston Celtics’ fourth-quarter execution the past two games can be summed up in one sequence.
After clawing their way back into Thursday night’s visit from the Philadelphia 76ers, Boston found itself down 3 with 25.7 seconds to go with the ball. But the Sixers applied full-court pressure and inbounder Jayson Tatum panicked a bit while waiting for Jaylen Brown to race back to receive the pass. Brown ultimately got tangled with Josh Richardson and fell to the floor as Tatum’s pass sailed wide and bounced out of bounds near the Sixers' bench.
Painful as it would have been, the Celtics could have burnt their final timeout. They could have simply handled Philadelphia’s pressure better and not fumbled the ball — and the game — away.
Ultimately, great teams find a way to win this sort of game. Or the one 24 hours earlier when Boston kicked away a double-digit fourth-quarter lead in Indiana.
Save the excuses about available bodies and bad calls and whatever else you want to blame. The Celtics, seemingly unflappable in the face of in-game adversity early in the year, wilted twice against primary Eastern Conference rivals the past 48 hours.
Because of that, Boston arrives at a very random five-day December break in its schedule at a respectable 17-7 overall, but with a bit of a sour taste from dropping two games against potential East playoff foes. The Celtics have slipped to fourth in the conference with Philadelphia executing a leapfrog after Thursday’s 115-109 triumph at TD Garden.
“We just have to learn how to win,” said Kemba Walker, who scored a team-high 29 points against Philadelphia but got limited to 8 points with only one field goal after the intermission. All this one day after Boston wasted a 44-point outburst when Indiana rallied for a 122-117 victory.
"We have a lot of lapses during these games. We have stretches where we’re playing super well. And then we have lapses,” said Walker. “We just have times where we’re just — it’s bad. It just looks really bad. So we just have to tone that down a little bit, just try our best to put a 48-minute games together. And that’s going to take everybody.”
Maybe it’s greedy to suggest the Celtics should win these sort of games. After an opening-night loss in Philadelphia, Boston ripped off 10 straight wins and had won six of seven entering this week’s back-to-back. These young Celtics had been so cool under pressure that it’s been a bit jarring to see them get sloppy and shoot themselves in the foot with mental miscues.
"I think, going in, when you look at the schedule you know this is going to be a tough one but, once you’re in the heat of the moment, you’re not really feeling those effects,” said Gordon Hayward, who departed Wednesday’s game in Indiana after getting hit in the nose but didn’t look overly hindered against Philadelphia.
"I think two emotional losses for us. Certainly, it’s tough in games that go down to the wire. I felt like we had chances in both. But it is what it is. It’s a long season, it’s part of it. We’ve got to try to learn from it and move on but we can’t blame it on legs. We’re professional athletes. We should be able to handle that.”
Yes, Marcus Smart would help in these situations. But the Pacers were playing without Victor Oladipo, and the Sixers didn’t have Al Horford, who got a standing ovation when shown on the Philadelphia bench at the start of the second quarter.
The Celtics, if they want to be honest-to-goodness contenders, need to win these sort of games. It was one thing to find a silver lining when they took the Clippers to overtime last month on the road but the last two games have lacked the defensive focus displayed during much of Boston’s early-season success.
To be sure, there are positives to pluck from these two games. Daniel Theis and Enes Kanter held up surprisingly well while jousting with Joel Embiid. Philadelphia’s All-Star big man finished with 38 points on 12-of-21 shooting with 13 rebounds and 6 assists. He did a nice job dominating in 1-on-1 matchups and showcased his passing skills while generating open looks for teammates when Boston sent multiple bodies at him.
Kanter turned in his best game of the year and Theis played well for much of the night. The duo combined for 36 points and14 rebounds, essentially negating Embiid’s output (though his impact went far beyond those two stat categories).
The next step for these Celtics is consistently staying poised in high-pressure moments. Players have to avoid careless turnovers, they have to be willing to work for good looks on the offensive end, and they can’t lose focus on the defensive side.
While it’s obvious the Celtics never consider themselves out of a game, they’ve got to be better when things get tense.
"One thing I love about us is that we’re not quitting. We’re still fighting through adversity,” said Walker. "When things are getting rough we’re not putting our heads down, man. We’re competing at a very high level. So it can only go up from here.”
Unfortunately for Stevens, it’s plays like the inbounds turnover that will gnaw at him until the Celtics get back on the practice court next week. Boston doesn’t play another game until Wednesday night in Dallas.
That’s a lot of time to ponder how Thursday’s game got away. And Wednesday’s before it.
“We didn’t get the ball [inbounds],” Stevens said after Thursday’s loss. "I think that’s obviously -- you gotta be able to do those things in the biggest moments and we didn’t get that done.”
Don't miss NBC Sports Boston's coverage of Celtics-Mavericks, which tips off Wednesday at 8:30 p.m. with Celtics Pregame Live, and then Mike & Scal have the call at 9:30 p.m. You can also stream the game on the MyTeams App.