In a meeting of the top two teams in the Western Conference, Durant hit two 3-pointers down the stretch to give the Thunder a 10-point lead with 68 seconds to play.
Durant finished with 36 points while hitting 12-of-22 shots from the field. He also had seven rebounds and five assists in what was Oklahoma City's fifth straight win.
Reggie Jackson scored 13 of his 27 points in the fourth quarter and Serge Ibaka had 14 points and nine rebounds. Oklahoma City handed San Antonio its fourth home loss of the season and also took over the best record in the conference.