It's just the second time in his career that the 35-year-old Lee has been on the disabled list. He was injured running to first base on Friday night.
He's played in 49 of Houston's 54 games this season and is hitting .297 with four homers and 23 RBIs.
Wallace hit .265 with 10 homers and 37 RBIs in 50 games for Oklahoma City this season. He was in the lineup at first base for Sunday's series finale against the Cincinnati Reds.