Kristaps Porzingis returned to the floor Thursday night in a Golden State Warriors uniform and called it “a good first game” after a 121-110 loss to the Boston Celtics at Chase Center.

The 7-foot-2 center finished with 12 points in 17 minutes in his debut following a trade from Atlanta, as Golden State fell to 29-26.

“I felt all right,” Porzingis said. “Far from being in perfect shape, but I think for first game back after a while, getting some energy back, feeling good.”

He said his rhythm improved as the game progressed, particularly during an extended stretch late in the third quarter and into the fourth.

“Yeah. I think as the game went on, it just felt better and better,” he said. “I think this is a good first step to keep building.”

Porzingis acknowledged there were areas that need refinement, especially after time away from game action.

“Obviously lower minutes, had some opportunities, couple of turnovers,” he said. “I think it’s just a matter of time to get in a better rhythm from this point on, but a good first game.”

The big man shared the floor with Al Horford and Draymond Green in different frontcourt combinations and emphasized that chemistry will come with repetition.

“I don’t know. It’s hard to say,” he said. “Obviously I know Al from the Celtics, and he knows me really well, so that’s going to be easy.”

On playing alongside Green, he added: “With how vocal and how experienced Draymond is, also, just a matter of time to find a good rhythm. He already knows my tendencies from just playing against each other.”

Porzingis stressed that familiarity grows through minutes.

“To get that rhythm you need a little bit of time on the court, and we’ll find it,” he said. “I’m a player that can find that rhythm pretty quickly.”

Facing his former team added another layer to the night, and he credited Boston’s structure under head coach Joe Mazzulla.

“You have to give credit to Joe and the coaching staff for sure,” Porzingis said. “Joe’s a great coach, great leader for them.”

He also pointed to Jaylen Brown’s impact.

“JB’s playing at a super high level leading them, and they’re a good team,” Porzingis said. “Even without JT and some of us that were there, they’re still a good team.”

On his conditioning, Porzingis made it clear he wants his minutes to increase soon.

“Honestly, as quickly as possible,” he said. “Even tonight, I would like to go even a little bit longer.”

He added: “I have to take it step by step. It’s a long-term vision. Just take it one game at a time, add a couple minutes next game hopefully, and keep building.”

Porzingis also addressed pregame movements that were visible before checking in.

“That was just to keep moving, keep the blood moving, just to stay warm,” he said.

Evaluating his own play, he remained direct.

“I always stay critical with myself,” he said. “Shot wasn’t perfect. Couple shots were a bit flat.”

He noted Boston’s defensive approach.

“They were doubling from the beginning and putting a smaller guy, making us kind of slow down,” Porzingis said. “Just doing a better job in all these small things, making the right read, not turning it over.”

On returning after time off, he said the adjustment felt familiar.

“It’s always weird coming back after a while,” he said. “I’ve had my ups and downs in my career and I’m pretty good at jumping right back in.”

He summed up the night simply.

“Felt all right for the first game back. Just want to keep building on top of this.”