Sal Zizzo (right) steals the ball away from Thierry Henry in their season opener on Sunday.
Don Ryan/AP

Portland Timbers midfielder Sal Zizzo will be sidelined four to six weeks following surgery on his left knee. Zizzo tore the medial meniscus during practice Monday and was operated on by Dr. Richard Edelson in Tigard.

The 25-year-old, in his third season with Portland, has one goal in 51 games. Portland announced the injury Tuesday.

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