Kristaps Porzingis has not yet returned to practice with the Celtics but has got back on the court for individual work as he continues to recover from his left calf strain. While he’s progressing, coach Joe Mazzulla said he’s unsure if he’ll return for Monday’s In-Season Tournament quarterfinal game against the Pacers.

“His status hasn’t been updated as far as if he’ll be ready for Monday, but he feels better than he did before,” Mazzulla said. “So I think we’re just trying to continue to take it day by day and see how it feels.”

Porzingis injured his calf in last Friday’s loss to the Magic, and Mazzulla had said the center would be re-evaluated after one week. He missed his third game since the injury on Friday against the 76ers.

Al Horford continued to start in Porzingis’ place. While Porzingis’ absence is certainly not ideal, Horford thought it could still serve serve some long-term benefits for the Celtics.

“It gives some of our other guys an opportunity to step in and play,” Horford said. “It also lets us see what some of the guys on the bench are able to do, how they’re able to play with us and be in there in meaningful situations and meaningful positions. So it just makes our group stronger. I think it’s an advantage. But it’s not something that we want to – we hope that he gets back soon.”

Sixers stars out

76ers stars Joel Embiid and Tyrese Maxey were both out for Friday’s matchup in Boston due to an illness. Maxey went through warmups to try to give it a go, but Philadelphia coach Nick Nurse cautioned that he was “really struggling.” Embiid did not participate in warmups.

Nicolas Batum – another Sixers starter – was ruled out due to a finger injury. Patrick Beverley and Marcus Morris each got a starting nod for the undermanned Sixers.

Warming up

Jaylen Brown was initially unsure about how to feel about the In-Season Tournament. He wanted to see how the first one shook out, and how it would be received around the league. And while he was outspoken after Tuesday’s win over the Bulls – which helped the Celtics advance to next week’s quarterfinals – about the ethics involved in how that game unfolded, he acknowledged that the tournament has been a success so far.

“It’s definitely generated the type of competition, the viewership that the league and the players association was looking for,” Brown said. “So I think that was the positive. I know the point differential is something that maybe is being talked about, but I think a lot of positives overall from the idea that has emerged now into being the in-season tournament.”

The NBA announced on Thursday that the group play stage of the tournament delivered increased ratings on both national and local TV. Group play games across ESPN and TNT averaged 1.5 million viewers, up 26 percent from last season’s comparable windows. The average audience on regional sports networks for the group play games were up 20 percent from last November’s average.

“I was probably just more curious,” Brown said. “It’s just something new, I wanted to see how the guys would respond to it. The older guys, the younger guys to see a review of what would be the feedback generally from the players and stuff like that. For the most part, I think everybody was kind of in the same boat. Like, they didn’t hate it, but they didn’t love it either. But as it’s starting to grow, I think people are starting to gravitate to it a little bit more. I’m thinking it’s been a good thing so far.”

Step brothers

Have Brown and Porzingis just become best friends?

Pardon the reference from “Step Brothers,” but it’s fair to ask after Brown included a photoshopped image of himself and Porzingis on the popular movie’s iconic poster in an Instagram post this week. It included the caption, “Bro better not touch my drums,” another reference from the movie.

“One of my friends sent it to me that has been following it,” Brown said.

Before Porzingis went out with his calf injury, he and Brown had been building an elite two-way game together to start the season. The duo has immediately connected since Porzingis’ arrival to Boston this summer, both on and off the court, as they live in the same building in Boston, too.

“Me and KP (have) been building some good chemistry, got a lot of highlight plays and stuff like that and I’m always looking for him since he’s been here in Boston,” Brown said. “It’s been a great contribution and I know he’s so important to what we’re trying to build. So I see it as like somebody that I want to be … have a good relationship and help make sure they have a good experience while they’re here.”

Apology received

Mazzulla said that he did get in touch with Bulls center Andre Drummond, who he said he was going to apologize to after Tuesday’s game. The Celtics, despite blowing out the Bulls, fouled Drummond intentionally twice during the fourth quarter in an effort to ensure they advanced in the in-season tournament by the necessary point differential.

“I apologize to Andre Drummond for doing that,” Mazzulla said after Tuesday’s game. “But it gave us the best chance considering the circumstances we were in.”

Scenarios announced

The Celtics’ next game comes Monday night at Indiana as they face the Pacers in the quarterfinals of the in-season tournament. If they win, they will head to Las Vegas for the semifinals, where they’ll face the winner of Bucks-Knicks on Thursday night.

If the Celtics lose, however, they will host a regular season game on Friday night against the loser of the Bucks-Knicks game. That game would start at 7:30 p.m.