The Daily Telegraph reported Brosque, 27, could possibly be ruled out for the rest of the season due to the problem which has restricted him since the start of the month.

Brosque, who is part of the 50-man provisional Australia squad for the 2011 Asian Cup, has been told by doctors he must rest for at least a month.

It's understood if Sydney's finals hopes are over by the time Brosque is due to return, he may rest to be fully fit for the club's 2011 AFC Champions League.

The Sky Blues man could be the latest striker to become unavailable for the January tournament in Qatar, following on from Archie Thompson and Joshua Kennedy, who is in doubt.