OKLAHOMA CITY — Kevin Garnett’s first shot Sunday, a 20-foot jumper near the top of the key, swooshed through the net as cleanly as so many of his jumpers that had preceded it.
Then the Celtics forward hit another, this one from 22 feet and closer to the right wing, and his shooting form looked solid.
The Celtics led, 8-4, over the Thunder at that point, and all seemed well for Garnett.
But his hot start turned cold fast, as Garnett missed 14 of his next 17 shots and finished with 10 points.
“It was crazy,” Garnett said after the Celtics’ 91-79 loss to Oklahoma City at Chesapeake Energy Arena.
“I was telling Paul [Pierce] before the game, ‘I felt good, my legs was under me,’ and for whatever reason, I just couldn’t put a whole game together as far as my body and mind and everything that I wanted to do as far as attacking.
“I thought I had a pretty good flow going early on. I just lost it, for whatever reason.”
When Garnett operated down low, he often faced up against his old teammate, Kendrick Perkins, the beefy center who now patrols the paint for the Thunder.
“I just tried to keep a body on him,” Perkins said. “He had some good looks, but I just wanted to contest all of them.”
Said Garnett: “Perkins didn’t do anything new. He was typical Perk.”
Kevin Durant, who scored 23 points, was impressed with Perkins’s work.
“That’s his mentor, the guy he learned a lot from and the guy he looked up to and he took the challenge by making him shoot tough 2s,” Durant said. “KG makes a lot of those and some of those shots he normally makes he missed.”
Celtics coach Doc Rivers said he wasn’t happy with Garnett’s shot selection.
“Those weren’t great shots,” Rivers said. “I want him to be aggressive, but we want to get him better shots than he did. He did miss some open shots, but I think I have to do a better job of getting him better shots.
“I would love him having 20 shots, but I’d like to have him take 20 good shots. I think [Sunday], he had 10 good shots and then 10 very tough shots.”
As expected, forward D.J. White signed a second 10-day contract with the Celtics. His first contract expired midnight Saturday.
Forward Shavlik Randolph is expected to sign his second 10-day contract soon; his current contract expired at midnight Sunday.
“All I tell Danny [Ainge] is I want them to stay, and Danny’s job from there, if he’s going to find someone else, he’s going to,” Rivers said before the game.
“I just like the continuity. We’ve had so much change over the last three or four weeks. I just like the continuity now. I don’t think there’s anybody out there that’s going to save the world, but both of those guys I think can help us in games. They’re getting more comfortable with what we do. I think it’s easier to go that route.”
Neither White nor Randolph has played much since joining the Celtics.
Perkins left the Celtics in 2011, but he said it’s still hard to play his former teammates.
“I think it’ll be easier when a lot of the guys I played with will be off the team,” he said. “It’s still pretty hard going against guys that I went to war with. We had great times over there. It’s not easy go against them, especially against a coach in Doc Rivers, who pretty much raised me and instilled in me who I was as a player.”
Rivers said of Perkins in Oklahoma City, “They needed that voice, they needed a voice here.”
Rivers added, “Perk’s numbers will never coincide with his productivity. You’ll look at his numbers and a lot of times, you’ll say, ‘What does he do?’ Well, I can tell you — a lot. He’s a great player to have on your team when you have great players on your team, because he knows what to tell them and he backs them up.
“It’s good to have an instigator, and I think we can put Perk strongly in the instigator category. That’s why I love him.”
Perkins came to Oklahoma City in a trade that sent Jeff Green to Boston, and Green returned to Oklahoma City on Sunday for the first time since that trade.
“Nerves was there, but at the end of the day, I wanted to win the game, so I wasn’t really thinking about too much else,” Green said. “It felt good just to get it over with.”
When Jason Terry checked into the game he was booed, a sign these fans haven’t forgotten that Terry played with one of their rivals, Dallas . . . When 38-year-old Thunder guard Derek Fisher checked into the game, Rivers called over to him, “No retired players!”
Baxter Holmes can be reached at email@example.com.