Less than five minutes into Thursday night’s clash of best vs. best, the Golden State Warriors were already threatening to pull away. They led the Celtics 15-6 after a pair of Kevin Durant free throws, and appeared to have already solved the formula Boston had used to fuel a 13-game winning streak.

As they often do when the offense grinds to a halt, the Boston Celtics turned to a reliable half-court play to settle in. It worked, producing a wide-open Jaylen Brown cutting down the baseline.

The second-year forward could have laid it in quickly and efficiently. He didn’t. Instead he opted for a quick spin and vicious jam, with a little flourish for good measure.

It was a small choice, made in the split-second it took for the play to transpire. It also set a tone, one that allowed the Celtics to survive its worst offensive night of the season against the best team in the NBA.

Later in the first quarter, Brown did what few are good (or brave) enough to do: he pressured two-time Kia MVP Stephen Curry into coughing up a loose ball. Just as rare, he pursued and won the possession in the kind of frenetic setting the Warriors usually feast. Brown got around Curry, controlled the ball before Zaza Pachulia could reach it, and sprinted down the other end for a tomahawk jam.

Another scene from the first quarter: Brown briefly lost Durant through a maze of screens, and the reigning Finals MVP rose for the mid-range shot he normally converts without thought. He didn’t count on 1) Brown not giving up on the play and 2) having the audacity to block his shot.

And that’s the way it went for the rest of the night. Whenever Kyrie Irving’s 4-for-16 night seemed to doom them, whenever it felt Jayson Tatum’s quiet showing (2-for-5 shooting) would leave Boston wanting, Brown did something to spark them.

It turns out the 21-year-old wasn’t just fighting the odds of scoreboard or opponent. Brown was also waging a battle with his heart, which was sorely tempted to mourn alone the loss of his best friend, who passed away on Wednesday night.

“I knew coming into today that he would have wanted me to play,” a quietly emotional Brown told reporters after the game. “After talking to his mom and family, they inspired me to come out and play. I wasn’t in any shape to come out. I wanted to be in my room.”

“I came out and played in his spirit today.”

Jaylen Brown pays tribute to his best friend after playing tonight's game in his honor. pic.twitter.com/js2a4RtpCs

— NBA on TNT (@NBAonTNT) November 17, 2017

Instead, Brown leaned on the escape of the game and the support of his teammates, rewarding both with one of the best performances of his young career. He finished with a team-high 22 points, seven rebounds, two blocks and two steals in 34 minutes of action. The effort was instrumental in extending Boston’s win streak to a league-best 14 games while also halting the Warriors’ own seven-game streak of dominance.

All of that was, of course, a footnote to the individual more focused on personal loss than the results of a game. Brown remembered clearly when his friend, Trevin Steede, reached out to him when he was a new transfer in high school, too introverted to make new friends.

“He walked up to me the third or fourth day and asked who I was sitting with [at lunch], even though I wasn’t sitting with anybody,” Brown recalled with a slight break in his voice. “He told me to come over and sit with him.”

That one was for you bro !! #RIP pic.twitter.com/Rnvy54Wsh2

— Jaylen Brown (@FCHWPO) November 17, 2017

After helping his team clinch its biggest victory yet, Brown let the knowledge that Steede was no longer there to sit with wash over him. Like that not-so-long ago day in high school, however, someone was there to reach out to him. It was Irving, embracing him after the final buzzer sounded, letting him know that others were there to fill the hole left in his life.

“I’ve lost individuals in my life. It’s never a good thing when someone else is going through it,” Irving said afterward, via MassLife.com. “You do your best to console and to encourage them, but at the end of the day, it’s about the strength within themselves and he showed a lot of that tonight, to be able to go out there and perform the way he did, I knew exactly where the game ball was going to.”

Facing a 17-point deficit, the defending champions, and the loss of a friend, there is no doubt that Brown earned it.