Los Angeles Galaxy midfielder Clint Mathis underwent successful surgery to repair a torn lateral meniscus in his left knee on Aug. 6, and will be out of action for three to six weeks. Mathis suffered the injury during the Galaxy’s 3-1 exhibition win over Mexican club Chivas of Guadalajara on Aug. 4. He got tangled with a Chivas player after a tackle just inside the penalty box near the end of the first half. Mathis currently leads the Galaxy in scoring with 16 points from seven goals and two assists. The Galaxy plays at California rival San Jose Aug. 7, and meets Columbus in the U.S. Open Cup quarterfinals Aug. 11 in Fullerton, Calif.