The right knee injury that Clint Mathis suffered during his MetroStarsÆ game last Saturday against the Columbus Crew will require surgery to repair torn meniscus. MathisÆ surgery is scheduled for July 17, after which he is expected to be sidelined for three to five weeks. Mathis also suffered a grade 1 sprain of the medial collateral ligament in his right knee. U.S. national team doctor Bert Mandelbaum will perform the surgery. He performed the surgery on MathisÆ torn ACL last June. That injury was also in MathisÆ right knee, but the current damage is considered unrelated.