Where to begin, where to begin, where to begin?

Maybe all they needed was a push. They shouldn’t have needed it. But maybe they did. Whatever the case, they got it less than two minutes into the second half, in literal form.

Marcus Smart could not have known the beast he would unleash when he took exception to a hard pick and sent Joel Embiid sprawling face first to the court with a two-handed shove to the back early in the third quarter. For the previous 24 minutes, the Celtics looked every bit a team en route to a runaway victory. The Sixers had experienced few halves of basketball more dispiriting than the one that had just transpired. It wasn’t just that they’d allowed 69 points, but that they looked utterly incapable of summoning the offense necessary to keep pace. The Celtics’ physical, picket-fence defense had again taken Ben Simmons out of the game, shutting off his driving lanes and leaving Embiid to shoulder the entire offensive load. Jimmy Butler and Tobias Harris might as well have been locked in a broom closet somewhere deep in the bowels of the Wells Fargo Center. For the 11th time in 13 games, there was no question about who the better team was. And with the playoffs less than a month away, the thought of winning a series against this team seemed a laughable proposition.

Truth be told, it might still be far-fetched. The Sixers got 37 points and 22 rebounds from Embiid. They got a herculean fourth-quarter effort from Butler. They spent the final two quarters facing a Celtics team that was missing three important members of its rotation (besides Smart’s ejection for shoving Embiid, Aron Baynes left the game with an injury, and Gordon Hayward did not play because he is in the concussion protocol). And still, it came down to a couple of plays that defied probability, Embiid somehow staying with Kyrie Irving long enough to make an off-balance left-handed block of a layup attempt, and Butler nearly losing the ball before drilling an 18-footer with five seconds left to ice what would finish as a 118-115 win.

The Celtics are a bad matchup for this Sixers team. In Marcus Morris, they have a player perfectly endowed to keep Simmons away from the rim. In Irving and Terry Rozier, they have two of the exact sort of guard that has long caused the Sixers’ perimeter defense fits. In Brad Stevens, they have a head coach who has already spent a playoff series devising ways to stop this franchise’s supremely talented yet odd-fitting cornerstones. The most favorable consequence of Wednesday night’s win might be the game it cost Boston in its quest to avoid opening up the playoffs on the road against the Pacers. In order to reach the NBA Finals, the Sixers might need to go around the Celtics rather than through them.

Yet there is also a chance that we look back on this second half of basketball as one of those seminal moments in the history of this current Sixers era. Embiid charging toward Smart, Smart urging him to come hither, teammates and referees intervening. It might not have been the moment that changed everything. But, after that moment, everything changed.

Embiid had already playing like a man possessed with the sort of internal drive that can single-handedly decide outcomes. He finished the first half with 18 points and 10 rebounds and was the only reason the Sixers’ 69-58 deficit wasn’t twice as large. But while Embiid may not have needed a push, the rest of the players undoubtedly needed something. This was especially true with regard to Butler, whom his bosses acquired specifically for situations like this: Simmons shut down, Embiid doing all he can do, the Sixers needing somebody capable of shaking a defender and creating scoring opportunities.

In the fourth quarter, it happened.

After a missing seven of his eight first-half shots, Butler emerged from the locker room with a more assertive role in the offense. In addition to his end-of-game dagger, he hit a couple of three-pointers in the waning minutes, finishing the game’s final period with 15 points.

Moving forward, the biggest question the Sixers face is how to get that man to show up more often in the first half. They are not a conventional team. They have a point guard who doesn’t break physical defenders down the way traditional ballhandlers such as Irving and Rozier can, and who needs to get to the rim to feel comfortable taking a shot. They have a shooting guard in JJ Redick, whom the Celtics spent the first half targeting on the defensive end of the court. Redick played one of his best defensive games of the season, but it was just barely enough.

At the same time, the Sixers got a win they badly needed. They beat a foe that should owe property taxes for space in their heads.

“I think it just gives us more confidence,” Simmons said. “We know that we can beat anybody in the league, it’s just a matter of doing it and having it on the paper and having that confidence going into playoffs.”

They got pushed, and they responded. This time of year, that counts for a lot.