The Seattle Sounders will have to once again have to make do without the services of Mauro Rosales. Coach Sigi Schmid revealed on Tuesday that his star midfielder has a sprained knee and will miss at least Friday's game and could be out as long as several weeks. Schmid said the injury was different than the one that cost Rosales most of the final five games of the regular season and both playoff games.

"We just have to see how he responds," Schmid said. "He could be out a couple of weeks. It could be a little more. We'll know in the next few days."

Rosales suffered the injury toward the end of Saturday's 3-1 win over Toronto FC when Aaron Maund took him out as the midfielder was attempting a shot on goal. Maund was not shown a card and no foul was even called.

Schmid mentioned several possibilities as possible replacements for Rosales. The simplest would probably be installing Christian Sivebaek or Roger Levesque at right mid. Schmid also suggested the possibility of moving Brad Evans to right mid, sliding Alvaro Fernandez into the central midfield and playing Marc Burch at left mid.

Of all those options, the most conservative would probably be playing Levesque. The most intriguing is probably Sivebaek, who saw his most extensive action on Saturday. In 25 minutes, Sivebaek showed some flashes of brilliance -- sending in a couple dangerous crosses -- but also illustrated that he still has some growing to do.