San Jose Clash forward Eric Wynalda will be sidelined for most of the Major League Soccer season after undergoing surgery March 10 to repair a knee injury suffered while playing with Mexican First Division club Leon. Wynalda, the all-time leading scorer on the U.S. national team, is expected to miss 5-6 months after arthroscopic surgery this morning revealed a torn anterior cruciate ligament and torn medial meniscus in his left knee. National team physician Dr. Bert Mandelbaum went on to perform reconstructive surgery, using a piece of Wynalda’s left patellar tendon. The operation, which lasted about 90 minutes, was performed at the Medical Plaza Orthopedic Surgery Center in Santa Monica. “My first thought, obviously, is for Eric. This is another in a series of unfortunate injuries for him,” Clash Coach Brian Quinn said. “We’ll do everything we can to help him get 100 percent healthy and regain his form.” Wynalda, 29, has been plagued by injuries during the past two seasons, playing in only 30 of the Clash’s 64 games. The three-time World Cup veteran, who has scored 32 goals in 101 international appearances for the U.S., led the Clash in scoring during the 1996 inaugural season, recording 10 goals and 13 assists, including the first goal in MLS history.