CARSON, Calif. (Jan. 10, 2009) - Defender Chad Marshall has been forced to withdraw from the national team camp in order to continue treatment on an injured right knee.

Marshall, who won MLS Cup with the Columbus Crew in 2008, had experienced discomfort prior to the start of training camp in January, and the symptoms have not improved during the first week in Carson.

Marshall will return to Columbus for treatment and further evaluation of his progress. The coaching staff is considering possible replacements.