The big-spending West Australian club, who signed Liverpool legend Robbie Fowler this week, have already filled their 23-man roster but haven't ruled out further signings with Carle on the radar.

Sage told The West Australian: "Obviously the salary cap becomes a constraint but it depends on a couple of issues."

The Perth owner revealed contracted players Adriano Pellegrino, Naum Sekulovski and Chris Coyne could depart the club, opening up space for Carle.

Sage added: "If those things happen there will be room in the salary cap for Nick and I've given Mitch and Fergie permission to go out and get him on that basis."

Pellegrino has been trialling in Scotland with SPL club Motherwell for the last fortnight, while Sekulovski reportedly has had interest from Hungarian outfit Ferencvaros.

And according to The West Australian, there is a possibility Coyne will extend his loan deal with Chinese Super League club Liaoning Whowin.

The Glory owner added the club wouldn't stand in Sekulovski's way if he wanted to explore an opportunity abroad, while acknowledging Pellegrino's move depends on the Scottish club.

Carle, who is currently playing in the English Championship with Crystal Palace, has an important weekend ahead with a relegation decider against Sheffield Wednesday on Sunday.

The World Cup hopeful has also been linked with a move to A-League champions Sydney FC who are understood to be after a playmaker following Steve Corica's retirement.