The Warriors turned the ball over six fewer times than did Boston and outrebounded the Celtics by 10, but shot just 34 percent in losing a third straight game. Golden State is 1-3 on a five-game road trip that ends on Saturday in Philadelphia.
Pierce scored 26 points and Jeff Green came off the bench to deliver 18. Golden State rallied from an early deficit to get within five early in the fourth period, but Boston ran off six straight points to create a comfortable cushion. The Celtics extended their home winning streak to eight.
Boston's Kevin Garnett scored seven points and his 13 rebounds moved him into 10th place on the all-time list.
Stephen Curry, who produced 54 points against New York on Wednesday, had 25 to lead Golden State. Curry, however, went just 6-of-25 from the field while making all 10 of his attempts from the foul line.