It isn’t easy being a depth player on a team like the Celtics. Your minutes are sporadic. You might go several straight games without seeing the floor at all.

But when you are called upon, be it as an injury replacement or to exploit a certain matchup, you’re expected to produce.

Jordan Walsh did that Friday in the longest look of his NBA career to date.

The 2023 second-round draft pick set or tied career highs in minutes (21), points (nine), rebounds (five) and 3-pointers made (2-for-2) in a 37-point drubbing of the Indiana Pacers. And it wasn’t just garbage-time stat-padding, either.

Walsh was part of head coach Joe Mazzulla’s regular rotation with Kristaps Porzingis and Jrue Holiday inactive, checking in during the first quarter for the first time since Dec. 4. He played more minutes Friday than he had in the previous eight games combined.

“It’s definitely a part of his development plan, and I think he’s grown a lot,” Mazzulla said before Sunday’s rematch against the Pacers at TD Garden. “One, his defense. He’s had some great physical defensive possessions, having an understanding of NBA defenses, the different coverages, the tendencies, and his ability to be active. His offensive rebounding has been really good. I think he’ll continue to work on his shot, which I think has gotten better.

“The biggest thing for young guys is earning a defensive identity, but also the respect of the players around you, and he does that with his attitude and his work ethic.”

Walsh, who has nine healthy DNPs this season, said it felt “amazing” to be as involved as he was on Friday.

“It’s great,” he said. “I could go six, seven games (with) DNPs, not playing, and then you’re thrown into a game like this expected to succeed and expected to excel in your role. So it can be tough at times, but always keep the mentality of, even when you catch three, four DNPs, that fifth game going in with the mentality of, ‘Oh, I’m going in at the three-minute mark, four-minute mark,’ whatever it is. Just always being ready.”

Though he’s still unlikely to see regular playing time when the Celtics are at full strength, Walsh’s development this season is reflected in his usage. After spending a large chunk of his rookie year with Boston’s G League affiliate in Maine, the 20-year-old has appeared in just one game for the farm club this season (after requesting to do so).

Walsh already has appeared in more than twice as many NBA games (22) as he did all of last season (nine).

“I’m super comfortable,” the 6-foot-7 forward said. “I used to get little butterflies, little nervous. But now it’s like, all right, I’ve got to go in, do my job, handle business. I’ve got a job to do, so that’s what I’m going in to do.”