“I think it’s just the rivalry,” a more subdued Pritchard said in the quiet locker room about an hour after the game. “Felt like I’m back in my college days [at Oregon] where I’m playing Washington or Arizona or something. Rivalry will bring that out of you.”

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Pritchard made 10 of 14 shots and 6 of 9 3-pointers, and finished with 30 points, 8 assists, and 4 rebounds. It was one of his most complete and efficient games as a Celtic, sparking a win that Boston fans will savor as much as any other this regular season.

“I think his confidence comes from his work ethic,” coach Joe Mazzulla said. “I think it also comes from his humility to be like, ‘This is who I am and this is what I have to do to get to where I want to get to.’ ”

Before the game, the Lakers unveiled a statue honoring former coach Pat Riley outside Crypto.com Arena. Riley guided Los Angeles to four NBA titles in the 1980s, with two of the victories coming against the Celtics.

He was joined by his former players including Johnson, Abdul-Jabbar, and James Worthy, and when addressing the crowd at halftime, he encouraged the Lakers to “beat some Boston [expletive].”

But that never transpired. Instead, the Lakers appeared frustrated and frazzled. They collected three technical fouls for voicing frustrations with the officiating, and whenever they took even a moment to complain, the Celtics quickly turned it into a five-on-four advantage and rushed upcourt for layups.

“Coming into this game, we were going to play fast,” Pritchard said. “Get it off the net and make them run.”

During the first quarter, the Lakers slowed the Celtics at times using a matchup zone defense that helped them hide mismatches involving players such as Doncic. The Celtics patiently found their way around those sets, with Pritchard leading the way.

Mazzulla said that at Saturday’s practice, Brown advised the younger players like Baylor Scheierman, Hugo González, and Jordan Walsh how to wear down this potentially flammable Lakers offense. Then they took turns pestering the Lakers with full-court pressure, and neither Doncic nor James could take over. They finished with 25 and 20 points, respectively.

Jaylen Brown had a game-high 32 points on Sunday.Katie Chin/Associated Press

In the second quarter, the Lakers were whistled for four quick fouls. During one sequence, a no-call on their end was followed by foul shots for Brown.

Reaves clapped his hands in the face of an official, leading to a technical foul. Marcus Smart, who took an elbow to the face from Brown but was called for the foul, continued the conversation, leading to another technical.

Still, the Lakers lingered for most of the first half before Pritchard sent the Celtics to the break with momentum when he poured in a deep 3-pointer at the buzzer that made it 60-50.

“I think he’s really kind of figured it out, how to get to his spots,” said Brown, who had 32 points on 10 of 28 shooting. “He’s shooting the ball well and he’s seeing the game well. So, Payton has been playing at an All-Star level. And I’m happy to see it. Nobody’s happier to see it than me. So we find ways throughout the game to trust him and allow him to run the show.”

The Celtics stretched their advantage to 14 by the end of the third quarter before the Lakers pulled within 86-77 early in the fourth. But Smart missed a 3-pointer that could have made it a six-point game and subsequently missed two more, dropping him to 0-for-7 shooting on the night.

At the other end, Pritchard remained in control. He hit a pair of shots in the lane before drawing two free throws on a drive, helping Boston push its lead back to 94-79. He put his final stamp on the game with 3:24 left when he stepped back and swished a 3-pointer from the right arc with the shot-clock running down, after which turned and yelled toward Miller, the NBC commentator, behind him.

“Me and Payton share the same mentality: dog,” Brown said. “So when I see him and he’s got that, you just get the hell out the way.”

Adam Himmelsbach can be reached at adam.himmelsbach@globe.com. Follow him @adamhimmelsbach.