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The first 16 minutes on Friday night went about as well as they possibly could for the Boston Celtics, who had a 28-point lead over the Brooklyn Nets early in the second quarter. But instead of cruising to another comfortable win against an Eastern Conference opponent, they were booed off the floor a few hours later after an embarrassing 115-105 defeat. 

With 7:23 to play in the second quarter, Jaylen Brown hit a layup to put the Celtics up 51-23. Over the remainder of the game, the Nets outscored the Celtics 92-54 to complete the biggest comeback in the league this season. The 28-point turnaround was also the largest comeback in Nets franchise history.

While the Celtics eventually lost the game in the second half, the real turning point was the end of the second quarter, when the Nets closed the frame on a 16-4 run. As many teams with big leads tend to do, the Celtics took their foot off the gas and lost focus, and the Nets took advantage. Nothing summed that up better than the final sequence, when the Celtics botched a simple inbounds play, which led to a buzzer-beating layup for Dorian Finney-Smith to cut the deficit to single digits going into the break.

The Celtics, for whatever reason, were never able to regain their focus or their intensity. During his broadcast interview in between the third and fourth quarters, Celtics head coach Joe Mazzulla even admitted that the Nets were "playing a little bit harder" than his team. 

"That was the first time we couldn't get it back," Mazzulla added postgame. "I thought throughout the year we've done a good job of maintaining our composure and our poise. In moments like that, when the other team starts to play well and changes their mindset, we just have to adjust to the environment. It's hard."

But it wasn't just a case of better effort. The Nets were making more plays on both sides of the ball as well. Mikal Bridges finished with 38 points, 10 rebounds and four assists, while Cam Johnson (20), Finney Smith (17) and Dinwiddie (17) all had at least 17 points. The Nets also forced 19 Celtics turnovers, which they turned into 21 points on the other end. 

"They beat us in every analytical category possible," Mazzulla said. "If we don't commit to the margins, no matter how hard we play, we're not gonna win. They got more 3s up, they got more shots up, they got more free throws, they got more offensive rebounds and they turned it over less. You can play as hard as you want, you're not gonna win like that."

The Celtics have dealt with inconsistency and bizarre results this season. They're 1-3 against the Orlando Magic, trailed the Indiana Pacers by 30 in a game they eventually lost by five, and were blown out by 33 points by an Oklahoma City Thunder team that was without Shai Gilgeous-Alexander

This, loss, though, is the worst of them all. They were at home, playing a team that just traded its two best players and had lost four in a row coming into the game and had a 28-point lead. But while many fans and media members are rightfully concerned about what such a collapse says about their playoff prospects, Tatum and Co. do not feel the same way. 

"We lost, it was tough. Disbelief? No, we didn't play well," said Tatum, who marked his 25th birthday with a shooting line of 10 of 23 from the field and 0 of 8 from 3. "They played better than we did, and usually you lose. So it's not disbelief, I don't even know if it's anger. We play too many games to be angry. Move on, get ready for the next one. It is what it is, essentially."