For Boston’s first In-Season Tournament game on Friday night, all of its stars were there. Jaylen Brown and Jayson Tatum scored 51 points together. Jrue Holiday was one assist away from a triple-double. It was easy for Kristaps Porzingis’ teammates to score because he was in the paint against a small-ball Brooklyn Nets side.

The real star of the 121–107 win, though, was Payton Pritchard.

“He changed the game for us tonight,” Joe Mazzulla, the head coach, said.

Pritchard scored 13 points, grabbed five rebounds, and gave out three assists in more than 30 minutes of play that didn’t have a mistake and was full of hustle plays.

Pritchard tied his career high with four offensive rebounds, making it a great day for him. This led to eight second-chance points, five of which were scored by Pritchard himself.

“Payton just changes the vibe of the game,” said Jaylen Brown, who scored 28 points and pulled ahead of everyone else. He’ll pick up the ball full court, make tough shots (he’ll even shoot from the parking lot if you let him), and bring the ball back to the basket very well.

In general, the Celtics had a great night when it came to offensive rebounds. They got a season-high 17 of them. Twelve of those boards came from the bench, with six coming from Luke Kornet. Because they worked harder on the offensive glass, Boston scored 29 second-chance points, which was the fourth most of any NBA team this season.

Besides his hustle play, Pritchard also got back on track after a rough shooting stretch. He started the night by hitting two of three shots from long-range. In his previous three games, he had gone 0 for 11 from the field.

Pritchard talked about his past problems: “I think it started to mess with my mind a little bit.” “But then I thought about what made me a good shooter in the first place, and I just worked on that.” It’s mostly just a game of the mind. It starts to have an effect on you, and you start to doubt your skills. You worked too hard, but I believe in myself.

They also believe in him as a team member.

Jrue Holiday said, “I think every shooter and every player is going to go through a shooting slump. The key is to stay positive, stay aggressive, and take the best shot you can.” “If you know P, you know that he can score whenever he wants.” He’s almost impossible to stop when he knows his 3-point shot is going in.

At times on Friday night, the bench as a whole, especially the trio of Pritchard, Kornet, and Sam Hauser, looked like they could not be stopped. They made 13 of 25 shots from the field and scored 35 points as a team. Hauser scored 15 points on 5 of 10 shots from deep.

Along with the stars, that group will be hard to beat when they are all working well together. And Pritchard’s job as a floor general is very important to their success.

“In the long run, it will be good for us that he plays well and is sure of himself,” Brown said. It’s a big part of what we do.