Tony Parker contributed 14 points with nine assists and Kawhi Leonard added 13 points and eight rebounds for the Spurs, who won a second road game in two nights and a fifth straight overall.
They were playing without starting center Duncan, who was given the night off.
Marco Belinelli and Patty Mills came off the bench to put in a combined 22 points for San Antonio.
The 76ers were led by with Evan Turner with 20 points.
Spencer Hawes supplied 17 points and 13 rebounds.
Boston schools pull out free condoms over wrapping complaints
Aaron Carter is still in love with Hilary Duff