Pierce supplied 18 points, 11 rebounds and seven assists for the Celtics, who notched a third straight win while improving to 11-18 on the road during a stretch of the schedule dominated by away games.
Kevin Garnett provided 18 points, six helpers and five boards, helping Boston pull away with a 12-2 run to begin the fourth quarter.
The 76ers got 19 points and 10 rebounds from Thaddeus Young in the loss.
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