Charles Lee was part of the 2023-24 Celtics team that won an NBA championship.

He believes this year’s Boston squad is even better.

Lee, who now coaches the Charlotte Hornets after one season as Joe Mazzulla’s top Celtics assistant, marveled at the C’s talent and depth before Friday’s game at TD Garden.

“They were good last year, and I feel like they got even better this year,” Lee said. “I think that the bench has gotten deeper. Seeing what Payton Pritchard’s been able to do this year, he adds so much to the team. Sam (Hauser) and Luke (Kornet), those guys have really contributed a lot, too, and then your main guys have continued to get better. Like, to see JT (Jayson Tatum) the first time that we played them in Charlotte, to see the poise that he has, the trust that he has in all of his teammates, just continuing to make the right pass over and over again.

“It’s a team with great depth that looks like they just did a great job of preparing, and I know Joe and the staff, they’re obsessed with just making sure these guys have all the tools they need for every situation.”

Wins over Charlotte in their final two regular-season games would give the Celtics a 61-21 record, three wins shy of last season’s record. Last year’s team won the Eastern Conference by 14 games and breezed through the playoffs; the current group will enter the playoffs as the East’s No. 2 seed and should face stiffer postseason competition from teams like conference-leading Cleveland and Oklahoma City.

Friday was Lee’s first time back at the Celtics’ home arena since he left to take over the rebuilding Hornets. Returning to Causeway Street brought back “a lot of joyous emotions,” he said.

“You’re building something in your first year, and to end the season here, it’s pretty special,” Lee said. “This is part of my journey, it kind of helped groom me to be ready for the position that I’m in now, and so just a lot of joy, a lot of gratitude when you walk in, because you’re like, man, I got to win a championship here, and I got to learn from so many people, and all the all the things that helped prepare me for this moment is pretty special.”

Since the season began, Lee has had “very little” interaction with Mazzulla, who famously avoids in-season chitchat with fellow head coaches for fear of giving away “psychological tells.” Mazzulla said in November, straight-faced, that Lee “breached NBA rules and came into the assistant coach locker room and forced me to give him a hug” before an early-season Celtics-Hornets game in Charlotte.

“I told Charles when he left, ‘I’m not talking to you during the season. I’m not waving to you at the national anthem. I’m not doing that. You’re an enemy,’” Mazzulla said then.

Lee, like the reporters in attendance at that news conference, couldn’t quite tell if Mazzulla was serious.

“I love that about Joe,” the 40-year-old said. “You don’t know if it’s for real or a joke. That’s why you build such a great friendship. I understand that in the heat of a moment or during the season, you are the enemy. If you’re not wearing a Celtics uniform or within the Celtics organization, he’s doing everything he can to prepare to beat you. In the summer, he might share some knowledge with me or some wisdom and we’ll grab a beer together or some wine.”