BOSTON -- Kristaps Porzingis participated in parts of Friday's practice -- the Boston Celtics' first since advancing to the NBA Finals earlier this week -- and coach Joe Mazzulla said he's pleased with the center's recovery from a right calf strain.

"He's getting better," Mazzulla said at the team's facility. "He's out there shooting. Went through a couple of drills in practice. So, progressing well and kind of confident where he's at right now."

Porzingis has been out for more than four weeks since suffering the injury during Game 4 of the first-round playoff series against the Miami Heat. Although Porzingis is a key cog at both ends of the court, the Celtics have still been able to go 9-1 without him, dispatching the Heat, Cleveland Cavaliers and Indiana Pacers to return to the Finals for the second time in three seasons.

After coming to the Celtics in a blockbuster trade last June that saw franchise icon Marcus Smart head out of town, Porzingis has averaged 20.1 points, 7.2 rebounds and 1.9 blocks per game this season. He has shot a career-best 51.6% overall while hitting 37.5% of his 3-pointers on more than five attempts per game.

Friday's practice was the first time since the injury that the media have seen Porzingis doing anything, even if it was only some movement 3-pointers that he did without any noticeable sign of a limp or hitch.

As far as Porzingis' availability for Game 1 of the NBA Finals on Thursday (8:30 p.m. ET, ABC), Mazzulla -- typically tight-lipped about injuries -- didn't give anything away.

"I'm confident where he's at on whatever day today is," Mazzulla said.

Mazzulla and the Celtics are also confident in their ability to prepare for the gauntlet that is the NBA Finals. Two years ago, when Boston faced the Golden State Warriors, the Celtics were a team lacking Finals experience. This time, the shoe is on the other foot, with every member of Boston's rotation having participated in at least one in their career, while the only Mavericks to have done so are Kyrie Irving and Markieff Morris.

Al Horford said the Celtics "absolutely" will benefit from their experiences two seasons ago.

"I think it is gonna help tremendously, because the first time, it felt like a roller coaster," Horford said. "Just a lot going on. The increased coverage of media and all the responsibilities that we had and just everything that came with it.

"So I just think that this time around, we all have an understanding. We know what things are like, and I feel like we'll be able to manage everything better."

The other thing the Celtics see as a benefit is the significantly fewer games this team has played in these playoffs -- 14 -- as opposed to two years ago, when the Celtics entered the Finals after having played back-to-back grueling series against the Milwaukee Bucks and the Heat.

Boston surely hopes that will be enough to help tip the scales in its favor and deliver a record-setting 18th championship banner.

"I mean, it takes everything," said Jrue Holiday, who won the 2021 NBA title with the Bucks. "I think it's one of the hardest things I've ever done. Mentally, physically, you're exhausted. Teams know each other so well at this point, it's kind of about making plays. It's about executing. I think for me the biggest thing is just how exhausted you were or how exhausted I was because I left everything on the floor.

"... I think being able to go out there and fight and leave everything out on the court, you have the best chance of getting that win."