Houston Rockets guard Tracy McGrady learned Tuesday he will miss three weeks while rehabbing his sore left knee.

Dr. James Andrews said McGrady is suffering from general soreness in the knee, which was surgically repaired last off-season. He had originally been ruled out for a week, but McGrady said after Tuesday's workout he would be out three weeks.

McGrady has missed the last three games with soreness in his knee. He has averaged 15.6 points and four assists through 15 games played this season.

The Rockets also will be without Brent Barry for the next two weeks after suffering a small tear in his leg muscle. The team also missed Shane Battier for the first 16 games, after he had off-season surgery to remove bone spurs.