BOSTON – The Boston Celtics have had one important constant during the recent rash of injuries — the Big Three are still healthy.

Kevin Garnett had 17 points and 14 rebounds Thursday night — one of the three Boston players with a double-double — to lead the Celtics to their 12th straight victory, 102-90 against the Atlanta Hawks.

Paul Pierce had 15 points and 10 assists, and Glen Davis added 18 points and 10 rebounds. Ray Allen scored 18 points and Nate Robinson had 14 for the Celtics (21-4).

“We feel we should win the game. On most nights we’re playing three or four All-Stars,” said Pierce, who played as a “point-forward” for much of the second half, handling the ball a lot and setting up Allen for open looks with solid passes.

Boston point guard Rajon Rondo missed the game after spraining his left ankle in Wednesday night’s victory at New York. He’s expected to be sidelined at least a week. Center Shaquille O’Neal was also out, missing his fourth straight game with a sore right calf.

The Celtics were already without Delonte West and Jermaine O’Neal.

It didn’t matter because Pierce, Allen and Garnett got just enough help from the role players.

The Celtics beat an Atlanta team that was called more athletic while defeating Boston in all four meetings last season.

“Kevin’s healthy,” Boston Coach Doc Rivers said was the difference in the games from last season. “You can stop there, and Paul’s healthy. The funny thing is it’s the younger guys getting injured.”

Garnett said the Celtics won’t let the injuries bother them.

“What are you going to do?” he said. “Quit? Put your clothes on and go home? That’s not what we do here.”

Marvin Williams had a season-best 26 points and Jeff Teague scored 18 for the Hawks.

“They still had three Hall of Famers out there,” said Hawks forward Josh Smith, who scored one point on 0-of-8 shooting. “I’m not making excuses but we still had two of our main scorers out also.”

The Hawks shot 50 percent for the game but were hurt by 18 turnovers.

Boston led by six points entering the final quarter but the Hawks closed within 77-75 on Teague’s one-handed runner in the lane.

The Celtics then scored seven straight points, with Davis and Semih Erden sandwiching baskets around a 3-pointer by Pierce, making it 84-77 with just under eight minutes to play.

Atlanta sliced it to 84-78 on Damien Wilkins’ free throw, but Pierce hit two free throws and Robinson nailed a 3-pointer, helping Boston pull safely in front. Allen’s 3-pointer made it 100-86 with 1:53 left.

“They know how to win and it’s where we need to get to,” Atlanta forward Al Horford said. “Give credit to Ray. In the second half he hit some big shots.”