Sydney FC have continued to rebuild their squad during the January transfer window with the signing of former Australian youth international, Robert Stambolziev.

The 24-year-old left-winger is the Sky Blues' third addition of the summer following the arrival of Senegalese internationals Mickael Tavares and Jacques Faty and comes in as an injury replacement for striker Corey Gameiro, who is out for the season.

The attacking player adds much-needed pace to Sydney's attack after a heavy injury toll that ruled out Gameiro and winger Ali Abbas for the rest of the campaign, but he might not be free to play against Central Coast Mariners on Saturday night.

Stambolziev has been having trials with Sydney for a number of weeks, but the club is still awaiting Stambolziev's international transfer clearance, which may not arrive until after the January 24 match.

"It's great to be able to bring in an attacking Australian player who will add depth to our attacking line-up," Sydney FC coach Graham Arnold said.