James Harden authored another classic performance in Game 4 of Sixers vs. Celtics, delivering a game-winning shot, 42 points, and an explanation for the performance that is only slightly short of divine intervention.

Let's go back to before Game 4 started to explain how it all ended.

• Prior to Sunday's Game 4, Doc Rivers told reporters he texted James Harden a link to a gospel song, titled, "Do You Know My Name?" The message from Rivers — who skipped over the idea that the song is probably about god and not the bearded No. 1 — was that the Sixers wanted James Harden to be, well, James Harden.

And the mention of this song postgame had Harden all out of sorts trying to dig up the text exchange, going through two different cell phones at the podium as he talked through the story. It was the first time Harden says he has ever received a link to a song from Rivers, and he figured he ought to take it seriously.

"I'm on the way to the game and I get a text from Doc and I'm like what's going on? It's a gospel song, and I'm like alright whatever," Harden said Sunday. "I just told my homies, let's play the song. Seven-minute song! I let the whole song play, and I'm like alright, there's got to be some kind of good juju in this song. However he's feeling, I want to feel like that. I guess it worked."

Whatever was needed to get him in the right frame of mind, the Sixers ought to repeat it before Game 5. The gap between Harden on Sunday and Harden in Friday's Game 3 was incomprehensible. Here was a player who looked so unsure of himself that he did not look at the rim during several noteworthy possessions in a loss, only to turn around and burn the nets down in a dramatic Game 4 victory. Whatever the final scoreline was going to be, Harden was going to go out battling, rather than deferring and meandering through the middle portion of the game.

According to Harden and the head coach, the key to that success (outside of a musical reminder) was Philadelphia's floor spacing. The Sixers were able to use ball screens to empty out sides of the floor for Harden, which meant that if he could break down the first line of defense, a path to the rim was there for him. Inside-the-arc struggles have been front-and-center during Harden's worst performances, and it was notable that his Game 4 started with two makes from five feet and in, Harden building momentum before he began unleashing a barrage of threes.

"Watching film and seeing what I could do better," Harden said regarding the bounce-back performance. "Guys set some really good screens, spacing was for the most part really, really good, it's a pretty simple game."

• Despite getting 42 points from Harden, it looked as though the Sixers would be heading to Boston down 3-1, one road loss away from the end of their season and (perhaps) the end of this Embiid/Harden partnership. Doc Rivers had just one timeout left for overtime crunch time after losing a challenge, so the ATO needed to be dazzling.

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In the end, the Sixers bet on simplicity.

"We thought if Tobias curled over the top, they've been switching everything," Rivers said. "And we told Tobias if they don't switch, you're going to have a layup. If they do switch, whoever's guarding Tobias is going to be on Joel. And that's good for us. We told James you just stand right there and if they come, be ready to shoot. Talking about trust, that's what it's all about right there."

It left Joel Embiid on an island against Jayson Tatum, with a hard-charging Jaylen Brown helping off of Harden in the corner. In the end, the catch-and-shoot jumper Harden has been reluctant to shoot for most of his career saved Philadelphia:

"I watched him this summer, we watch him every day, he works on it," Rivers said. "But it's something he hadn't done his whole life. And the last shot to win this game was a catch-and-shoot shot from James. It should tell every freaking kid, work on your weaknesses, keep working on them, you never know."

The Celtics will regret several decisions here, starting with their personnel, as Robert Williams III not being in the game felt a bit strange in the circumstances. But the Sixers only needed to beat the team in front of them, not the hypothetical best five Boston could have had in the game.

• On the subject of weaknesses, Joel Embiid's struggles against Al Horford came roaring back in this one. This looked like a game where he might finally put a statement playoff performance against the Celtics on his resume, with Embiid dominating through the first 2.5 quarters or so. What followed was one of the worst stretches of his playoff career, an impotent fourth quarter where Embiid went 1/6 and got held down by Horford in another big spot.

Embiid, who said he had "no lift" while discussing the struggles at the end of the game, was direct about his poor closing effort in this game. 

"I was terrible tonight," Embiid said. "I got to be better, I will be better."

The final stat line for Embiid — 34 points, 13 rebounds, four assists on 11/26 from the field — ends up flattering the big man far more than his performance deserves. Three of those five fourth-quarter misses were blocked by Horford outright, two with Horford as the primary defender and one with Horford coming in late as a help defender. It was  about as ugly as crunch-time basketball gets, rendering any suggestion that Embiid might have "solved" Horford this season meaningless.

• In the midst of Embiid's struggles late in the game, the big man got an absolute earful from veteran forward P.J. Tucker, which was picked up on the cameras during the broadcast of the game.

It came at a point when Embiid was beginning to look spooked, unwilling to attack with the same gusto he had just a quarter or two prior. And while we got multiple sides of this story after the game, Tucker was short and to the point with his delivery. 

"Nobody can guard Jo one-on-one, there's no way. I'm sorry, there's no disrespect to Al or anybody else, but I guarded him for a lot of years and when he's aggressive and assertive, it's impossible," Tucker said Sunday. "And I'd seen two or three plays in a row not do that, and we can't have that. Not with the season on the line, we can't have that."

Tucker's voice and toughness on the floor ended up being key factors for the Sixers late in the game. That moment with Embiid came immediately after Tucker pulled down a critical offensive rebound before scoring an and-one layup, knotting the score up with about a minute to play in regulation.

"The three-point play is just will, determination, wanting to win," Tucker said. "I had just gotten back in the game, so I had to leave an imprint somehow."

• A bit of VH1 Behind The Music with playoff media — there are a lot of jabronis in the room trying to get their shine before moving on to the next big sporting event on the calendar, which lends itself to some interesting moments in the press room.

Doc Rivers was thrilled by P.J. Tucker's performance late in this game, viewing his arrival as one of the key differences between this year's team and the group that fell in round two against Miami last year.

"There was a guy named P.J. Tucker on Miami," Rivers said. "There's a guy named P.J. Tucker on our team now."

As Doc Rivers finished that second sentence, a man in the thicket of reporters blurted out, clear as day, "That's why you got him!" 

It was so jarring that the only thing I can think to compare it to is Howard Dean's infamous BYAAAHHHHH that derailed his progress in the 2004 Democratic Primary:

Sorry, maybe no one cares about this except for me, but it was unbelievable. 

• Had the Sixers lost this game, there would have been a lot of attention on Jayson Tatum's potential game-winner in overtime, one that he earned with what looked like a clear push-off against Tyrese Maxey.

Doc Rivers was incensed by the non-call after the game.

"Jayson Tatum's three was awful that that wasn't called," Rivers said. "The reason it bugged me because, at the end of the game there were these touch fouls, Jayson Tatum has a 360 foul. Marcus Smart and Tuck get tangled up, touch foul. So if we're going to call it that way, you have to call that. To me, you've got to call that play."

It was not the only controversial whistle, with Rivers losing a challenge on a block/charge decision that you could at least argue had the chance to go either way. We'll see who the Sixers draw from the officiating pool on the road for Game 5, and where we end up after a topsy-turvy start to this series.

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