Danielle Robinson poured in a game-high 36 points 94 win over the Tulsa Shock at the BOK Center.
Jia Perkins dropped 22 points and shot 4-of-7 from three-point range and Roneeka Hodges added nine points off the bench for San Antonio, which finished the season at 18-16 and will head into playoffs as the fourth seed in the Western Conference.
Andrea Riley and Sheryl Swoops both netted 20 points and Tiffany Jackson added 19 points and nine rebounds for the Shock, which lost six straight to finish the season with a 3-31 mark, the worst single season record in WNBA history.
Leading 71-67 after three quarters, the Shock were outscored 23-19 in the fourth to send the game into overtime tied at 90.
In Overtime, San Antonio took control, outscoring the Shock 12-4 and shooting 62.5 percent. Amber Holt and Liz Cambage scored the only buckets of the OT period for Tulsa, which shot only 11.1 percent from the field.