The Suns got their first victory with Shaquille O'Neal in the lineup. They lost 130-124 to the Los Angeles Lakers in O'Neal's Phoenix debut on Wednesday night.
Steve Nash added 18 points, including a pair of late 3-pointers, and Grant Hill had 14 points and 13 rebounds to record consecutive double-doubles for the first time since Dec. 2-4, 2002. O'Neal had just four points but 14 rebounds as the Suns dominated the boards 50-32.
Kevin Garnett scored 19 points, Paul Pierce was 2-for-13 shooting for five points and Ray Allen scored 11 points and shot 3-for-12.
The Celtics never led while falling to 0-3 on their five-game trip through the West after going 16-0 against the Western Conference. Phoenix improved to 22-2 against the East.
The Suns played most of the game without Leandro Barbosa, who got a cut above the right eye on a shot from Pierce with 4:36 left in the game. The cut required three stitches and Barbosa did not return.
Phoenix went 12:05 without a field goal in the first half and still had the lead, 27-26. Nash ended the drought with a layup that ignited a 16-2 outburst that gave the Suns a 43-28 lead when Raja Bell made one of two free throws 1:05 before the break. Boston's Rajon Rondo made a layup with 2.1 seconds to go to make it 43-30 at the half.
It was the fewest points in a half by Boston and the fewest by a Suns' opponent this season.
Boston trailed by as many as 16 in the third quarter. The Celtics cut it to nine early in the fourth quarter and seven in the final seconds.
Phoenix led by 13 at the break despite committing 15 turnovers in the game's first 17 minutes.