"I think we're right where we want to be, especially on the road," said Rajon Rondo, who had 15 points and four steals as his team moved to 9-1 on the road. "We've got to clean up home."
Garnett scored nine consecutive points, including three dunks, to put Boston in command in the first 5 minutes of the second half. His two-handed alley-oop jam, which followed a pair of right-handed dunks, pushed the lead to 18 at 71-53 and the Thunder were never closer than 15 after that.
Boston shot 59 percent through the first three quarters and outscored Oklahoma City 28-16 in the third period -- with Rondo (13) and Garnett (11) doing most of the damage as coach Doc Rivers went to a spread pick-and-roll offense that the Thunder couldn't contain.
"Even though there were five guys on the floor, it was almost like they were playing a two-man game for the most part," Rivers said.
Durant scored 36 points -- accounting for half of his team's scoring 3 1/2 minutes into the fourth quarter -- before making an early exit with the rest of the Oklahoma City starters. But the usually mild-mannered Durant also picked up what he believes to be his first career technical foul for arguing a foul called against him late in the third quarter.
According to STATS Inc., the only other technical foul of Durant's career came Jan. 2 against Denver when he and the Nuggets' Dahntay Jones were assessed double technicals.
"I shouldn't have got fired up that much. That's not me," said Durant, who's in his third year in the league. "But I'm so passionate about the game, and I felt that it didn't go my way. I shouldn't have pouted like that and got upset.
"One technical out of almost 200 games, I guess I'll take that."
Durant shrugged off a shove from Garnett earlier in the game and didn't have much of a reaction to it in the locker room either -- "It is what it is," he said. "In between the lines, nobody's going to fight. Nobody's going to get into any tussles."
But he didn't think the Celtics got the best of the Thunder for being more physical either.
"They just talk. That's one thing we don't try to do is just talk," Durant said. "They're a physical team. Give them that. They're a great team. But they do a lot of talk on the floor, which I think that's kind of false toughness. They get in some teams' head. I don't think they did it to us."
Still, Oklahoma City suffered its most lopsided loss at the Ford Center this season.
The dominant performance earned all of Boston's starters except Ray Allen a rest on the bench for the fourth quarter at the end of one road trip but with another looming. The Celtics will return home to play Milwaukee on Tuesday before three more away games.
"It's really strange when you play these games on the road, you come home for one game -- I guess to unpack and re-pack -- and then you go right back out there," Rivers said.
Boston won its seventh straight game to improve to 16-4 on the season, a half-game better than Orlando for the best record in the East.
"Almost there," Rondo said when asked if the Celtics were playing exactly how they hoped. "Not complete, but we're putting [it] together. It's not just one quarter now. We're putting a couple quarters together. We're not quite to 48 minutes but we're almost there."
Russell Westbrook had 15 points for the Thunder.
The franchises have been linked since the trade of Allen on draft day in 2007 helped put the Celtics on their way to the NBA title. Oklahoma City has been rebuilding around Durant and Jeff Green -- their top-5 picks from that draft -- ever since.
The Thunder are off to a promising 10-9 start after a miserable 2008-09 season but got another reminder of the work that's left against the Celtics.
Durant entered the game needing only seven points to become the second-youngest player in NBA history to reach 4,000 career points. He got there with a jumper from the right elbow with 6:05 left in the first quarter, but the Celtics had already asserted themselves by then.
Durant's jumper snapped a 10-0 run featuring back-to-back 3-pointers by Pierce that put Boston ahead 19-10, and the Celtics wouldn't trail again.
The only player to reach 4,000 points at a younger age than Durant was LeBron James -- at 20 years, 318 days. Durant made it at 21 years, 66 days. Kobe Bryant, who had his record broken by James, was 21 years, 216 days when he scored his 4,000th point. ... The Celtics' 31 points in the first quarter were their most in the opening period this season. ... Boston, which has a 13-1 record on other days of the week, moved to 3-3 on Fridays.