Victor Wembanyama finished with 12 points, 13 rebounds and six blocks but made just one of 13 field-goal attempts. Ten of his points came at the free-throw line. The Spurs got 24 points from Stephon Castle, 18 from Dylan Harper and 14 from De'Aaron Fox, but their second-half push could not erase Oklahoma City's early advantage.
The Thunder made 10 of 14 three-pointers in the first half and took a 65-44 lead into the break. Their lead had reached 26 points at 59-33. San Antonio scored only 16 points in the second quarter, leaving itself a substantial deficit against the team it eliminated in last season's Western Conference finals.
The Spurs recovered offensively in the third, scoring 36 points to pull within 93-80 entering the fourth. Harper helped them continue that push, and his two free throws with 5:25 remaining cut the Thunder's lead to 102-94.
Holmgren answered with a tip-in. Castle then made a three with 4:18 left to bring San Antonio within seven at 104-97, but McCain immediately restored a double-digit lead with his sixth three-pointer. Gilgeous-Alexander followed with a pull-up jumper, Isaiah Hartenstein scored inside and Williams added a free throw. That eight-point run made it 112-97 with 1:56 to play.
Gilgeous-Alexander finished 13-for-27 from the field and added five rebounds, four assists and three blocks. Oklahoma City made 14 of 31 three-point attempts overall, compared with San Antonio's 10 of 37. The Spurs shot 36-for-93 from the field, or 38.7%.
Rookie Aday Mara supplied seven points and a block in his NBA debut. His third-quarter stretch included a rejection at the rim and a two-handed alley-oop, giving the Thunder another contribution from their second unit.