Stoudamire played 22 minutes, finishing with 11 points in the Spurs' 116-89 victory.
Stoudamire signed with the Spurs on Saturday after negotiating a buyout from his contract with Memphis, where he was playing behind two younger teammates in the Grizzlies rotation.
He has averaged 13.8 points and 6.3 assists in his 13-year career, and was averaging 7.3 points and 3.9 assists in 29 games for the Grizzlies this season.
But he hadn't played since Dec. 30, when he faced the Spurs.
The addition is expected to give defending NBA champions more depth while Tony Parker nurses a left heel injury.