Splitter, from Blumenau in Santa Catarina state, led the way with 21 points and 10 rebounds, while Gary Neal contributed six assists.
Known for their clinical and frugal approach, the Spurs shot over 50% from the field, while conceding just 12 turnovers to the Thunder’s 19.
The Spurs are now 49 wins and 15 losses, turning around a 10-point quarter time deficit with a stunning 35-point run in the second period.
Oklahoma, led by 26 points from Kevin Durant, has slipped slightly off the pace at 47 wins, 17 losses.
San Antonio was coming off one of its worst-ever home losses, beaten 136-106 by Portland on Friday.
The Spurs next play Minnesota in Minneapolis on Tuesday, March 12.
Full report at the NBA website.