The Thunder closed within a half game of the Spurs for the best record in the Western Conference.
Oklahoma City finished the game on a 13-4 run after the Spurs had moved within three points midway through the final quarter.
Westbrook scored 27 points to go with his seven rebounds and seven assists. Durant had nine rebounds along with his 25 points.
The Thunder hit 12-of-24 from 3-point range and held the Spurs to 40 percent shooting.