DETROIT — Two minutes into the Celtics’ season-opener against the Pistons on Tuesday, Derrick White missed a 3-pointer before Jordan Walsh streaked in and tipped the offensive rebound to Paul George, who was unmarked on the left arc.
George has become accustomed to making difficult shots under duress throughout his career. But in this case, as he lined up his first shot as a Celtic, he had time to set his feet, measure the distance, and focus before drilling the 3-pointer. It was the start of a spectacular day for George, who erupted for 38 points, a franchise record for a debut. He also added five steals.
George could not enjoy the performance as much as he had hoped, however. While he was finding his footing with his new team, the Celtics coughed up a 22-point second-half lead on their way to a puzzling 121-113 loss.
But George, acquired from the 76ers in the Jaylen Brown trade last summer, at least provided hope.
“He was unbelievable,” Celtics forward Jayson Tatum said. “Just the confidence he played with. Obviously making plays on defense. Just kind of getting to his spots. His ability to defend and get out and run and be able to space the floor and attack certain matchups how he can.”
George has battled injuries throughout his career and reached the 60-game mark just once in the last seven seasons. He was limited to 37 games for Philadelphia last year, in part because he received a 25-game suspension in January for violating the NBA’S anti-drug policy. George said he took medication while getting treatment for a mental health issue and was unaware that it was a banned substance.
Now, though, he said he feels healthy, and even at 36 years old, he is eager for a sustained run with a team he feels can challenge for a conference title.
“The last two years were very difficult trying to play through injuries and just not quite being 100 percent,” George said. “And this summer was huge. I had a great summer, had time off. And coming into this year, I knew it was going to be a big one. It was going to be a fun one, a great opportunity. And so I was just happy that I was able to attack this summer with working on my game more so than rehabbing and working on my body. So it was a great summer for me. And that was, I guess, the beauty in the process.”
George appeared in just two preseason games and did not look as dominant as he did on Tuesday. He made just 5 of 20 shots during the exhibition slate and averaged nine points. In addition to getting back into game shape, he said he struggled while trying to digest the schemes and language of a new system. He called it a “rough camp.”
“I think it was more getting back into the swing of things, playing again,” George said. “I thought really the camp legs were just heavy. I was winded a lot of times. So it was taking away the ability to kind of do things when I just felt a little heavy and sluggish. But I’m getting my wind back. I’m getting my legs back. I feel like I’m getting my pop back. And so that was kind of the difference maker.”
The Celtics were outscored by 17 points during George’s 17:35 on the bench. He played 30:25, which is about where the Celtics would like him to be as they show caution during a long regular season. Despite Tuesday’s loss, George’s play provided reason for optimism.
“Credit to these guys, though,” George said. “They did an amazing job keeping me in the loop, making me feel a part of the team at all points throughout this process. [Coach Joe Mazzulla], for making the game easier for me. [Derrick] White, Payton [Pritchard], [Tatum], all of those guys. All of them are collectively a part of me feeling confident and playing with rhythm out there.”
Adam Himmelsbach can be reached at adam.himmelsbach@globe.com. Follow him @adamhimmelsbach.