Tony Parker and Stephen Jackson led the Spurs with 16 points apiece. Tim Duncan had 11 points on 5-for-15 shooting, taking 11 of San Antonio's first 25 shots as the offense went through the All-Star center instead of Parker.
San Antonio had been averaging 109.4 points during its month-and-a-half winning streak and had been held to double digits only twice.
The Spurs, who already set an NBA record for the longest winning streak carried over from the regular season into the playoffs, were trying to match the league mark for most wins to start the postseason. The Lakers won 11 straight to start the 1989 and 2001 playoffs, getting swept in the NBA Finals the first time and winning it all the second.
The Spurs' last loss was to the Lakers at home on April 11.
Parker and Duncan didn't play in the final 15 minutes, and coach Gregg Popovich pulled the plug after another series of three straight turnovers allowed the deficit to reach 23 points early in the fourth quarter.
Sefolosha had a dunk off a lob pass from Russell Westbrook, who followed with his own two-handed jam on an alley-oop pass and Sefolosha followed with a reverse layup on another turnover-fueled fast-break chance to push the lead to 86-63 with 9:48 left.
The Thunder put together another 9-0 run coinciding with Manu Ginobili coming out of the game, and featuring Serge Ibaka sticking his tongue out after nailing a jumper from the top of the key. Coach Scott Brooks soon followed suit and pulled his own front-line players with the game well in hand.
* Basketball Hall of Famer Jack Twyman, one of the NBA's top scorers in the 1950s who became the guardian to a paralyzed teammate, has died. He was 78.
Twyman died Wednesday at a Cincinnati hospice of complications from an aggressive form of blood cancer, his son, Jay Twyman said Thursday.
Jack Twyman played for the University of Cincinnati and spent 11 seasons in the NBA with the Rochester and Cincinnati Royals. He averaged a career-high 31.2 points per game in the 1959-60 season, playing in six All-Star Games.
In 1958, after teammate Maurice Stokes was left paralyzed after a head injury suffered during a game, Twyman became his guardian to help Stokes receive medical benefits.
Twyman scored 15,840 points in his career and was inducted into the Hall of Fame in 1983.