Tony Parker added 16 points and the Spurs extended their longest winning streak since last December, when they climbed back up the standings after a similar slow start last season.
Andre Iguodala had 21 points for the Sixers, who dropped their sixth straight. But the skid is being overshadowed by speculation that Philadelphia may bring Allen Iverson back to the city where he became an NBA star.
Sixers coach Eddie Jordan acknowledged before the game that Iverson has been discussed, but emphasized that talks have been just that and nothing more.
Jordan also wanted the Sixers to focus on winning instead of the Iverson chatter, and despite the loss, Philadelphia hardly seemed distracted. The 76ers got as close as five points late in the fourth before San Antonio pulled away.
Willie Green scored 17 points and Thaddeus Young had 16 for the Sixers, who are off to a 5-12 start and have the third-worst record in the Eastern Conference.
A person with knowledge of the Iverson talks told The Associated Press on Saturday that the Sixers were approached about signing the recently retired guard. The person spoke on condition of anonymity because talks have not been made public.
Iverson's statement this week about ending his NBA career after 13-plus seasons hardly sounded like his mind was made up. Saying there is "a whole lot left in my tank," Iverson said he felt strongly he could still compete "at the highest level."
Iverson spent his first 10 years in Philadelphia and led the Sixers to the NBA finals in 2001. If the Sixers signed him, it wouldn't be for nostalgia: injured starting point guard Lou Williams is expected to miss eight weeks, and 19-year-old rookie Jrue Holiday is starting in his place.
Jordan said before the game that although Iverson has been discussed, the Sixers still want to see if their depth can pull them out of their tailspin.
"I have not been oversaturated with Allen Iverson in my mind or in conversations with our front office," Jordan said. "It's like any other free agent out there. We've talked about a number of people."
Spurs guard Manu Ginobili played for the first time in six games because of a strained left groin and came off the bench to score eight points in 17 minutes. Matt Bonner had 16 points.
DeJuan Blair had 11 points and 10 rebounds, and made his most memorable mark with dazzling successive plays on both ends in the second quarter. It began with Blair, hopping below the basket, hitting a bank shot while falling down on his back in the paint.
The 6-foot-7, 270-pound rookie then rumbled down court in time to spike Royal Ivey's layup attempt into the second row, leading a wide-eyed Duncan to spring off the bench and prompting a standing ovation for the quickly emerging fan favorite.
The Spurs have been on a roll since a skid of three straight losses dropped them to 4-6, their worst 10-game start in the Duncan era. But San Antonio has been dominant since.
The schedule might be helping. Only one of San Antonio's last five wins have come against a team that entered Sunday with a winning record, but the Spurs are about to be tested. San Antonio will play Atlantic division leaders Boston on Thursday and Denver on Saturday.
NOTES: Sixers F Elton Brand missed his third consecutive game with a sore right hamstring. Jordan said Brand could still wind up playing the final three games of this four-game road swing for Philadelphia.