The Thunder moved into a tie with San Antonio for the best record in the Western Conference at 56-20 and Oklahoma City holds the tiebreak advantage.
Durant scored 34 points and grabbed nine rebounds, then sat out the fourth quarter. Westbrook had nine assists to go with his 24 points.
Indiana leads the NBA in rebound margin, but Oklahoma City outrebounded the Pacers 53-31.
Roy Hibbert led Indiana with 22 points. The Pacers missed out on a chance to clinch its first division title in nine years.