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.
"It's not about Tony," Spurs coach Gregg Popovich said. "It's about our team, and we played much more poorly tonight than we have and I thought they played fantastic basketball in every way."
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 hadn't lost since April 11 against the Lakers at home. They had been averaging 109.4 points during the winning streak and had been held to double digits only twice.
"They played like it was a closeout game, both offensively and defensively," Popovich said. "They were very active, physical, they moved the ball well on offense. They did all those things better than we did. They beat us good."
Parker and Duncan didn't play in the final 15 minutes, and Popovich pulled the plug after a series of three straight turnovers allowed the deficit to reach 23 points early in the fourth quarter.
Sefolosha had a right-handed dunk off a lob pass from Russell Westbrook, who followed with his own two-handed jam on an alley-oop pass. Sefolosha followed with a reverse layup on another turnover-fueled fast-break to push the lead to 86-63 with 9:48 left.