Spencer Hawes had 17 points and seven rebounds and Evan Turner added 12 points and eight rebounds for the Sixers, who won their first preseason game on this side of the Atlantic Ocean after playing two earlier this week in Europe.
Jared Sullinger had 19 points and nine rebounds for the Celtics, who dropped to 0-3 in the first preseason of coach Brad Stevens.
The Sixers opened an 18-point halftime lead as first-year coach Brett Brown's starters were 21 of 30 from the field (70 percent) and accounted for 46 of the team's 54 points.
The Celtics got within 84-79 on a 3-pointer by Gerald Wallace with 5:30 to play but never got any closer in the game played at the University of Delaware.
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NEWARK, DE - OCTOBER 11: Darius Morris #7 of the Philadelphia 76ers goes to the basket against the Boston Celtics...
(Photo by Jesse D. Garrabrant/NBAE via Getty Images)