Danny Green had 14 points, Tiago Splitter scored 13 and Tony Parker and Kawhi Leonard added 12 each for San Antonio, which avoided another disappointing collapse against the Mavericks in less than a week and won at home against Dallas for the ninth straight time.
Monta Ellis and Tyson Chandler had 10 points each to lead the Mavericks.
Ellis injured his right knee with 6:43 remaining in the third quarter and did not return. He was played 22 minutes after scoring 38 points in Dallas' win over San Antonio three days earlier.
San Antonio (46-26) extended its lead to 1 1/2 games over Dallas (45-28) for sixth place in the Western Conference and evened the teams' season series at 2-2.