Kudos to the Spurs if they can beat the Thunder under these circumstances, which are being rusty and severely short-handed. 
San Antonio hasn't played in 10 days due to a COVID-19 outbreak that hit its team. Among the rotation players out for the Spurs are Rudy Gay and Derrick White. Making it worse, though, for the Spurs is leading scorer DeMar DeRozan, their best player, also is out for personal reasons following his father's death.
Remember, too, the Spurs' top big man, LaMarcus Aldridge, has missed the last six games because of a hip injury. He's questionable. San Antonio not only had to deal with COVID, but also the city and state of Texas enduring a winter storm that left many without power or water. So the Spurs' concentration level might not be where it needs to be. 
Oklahoma City is not a good team by any means. But the Thunder are capable given the right circumstances. They upset the Bucks three home games ago and they hold a backcourt edge on the Spurs with DeRozan out with the tandem of high-scoring Shai Gilgeous-Alexander and promising rookie Theo Maledon.