Adrian Mierzejewski complains about Sydney FC 'situation'

Adrian Mierzejewski's future at Sydney FC could be in doubt after the star midfielder hinted at a rift between himself and the A-League club.

The former Polish international signed a three-year deal with the Sky Blues last year and proved an immediate success, scoring 13 goals in 24 appearances and winning the Johnny Warren Medal.

But the 31-year-old is clearly disgruntled, complaining on Twitter about a "situation" he seems desperate to resolve.

It's not the first time he has used social media to suggest a potential dispute.

Two weeks ago he tweeted: "I can only say that after such a good season I had I only wanted to rest and spend time with family preparing to new season but now it's impossible."

"Soon I will be able to explain my position so that everyone could put themselves in my shoes and understand why I am having such a hard time right now... without my fault."

AAP has reached out to Mierzejewski to clarify his comments.

Sydney FC, meanwhile, has declined to respond.

Shortly after Mierzejewski's tweet, CEO Danny Townsend wrote: "As stated previously -- out of respect and common courtesy we will not publicly play out personal negotiations."

Mierzejewski is currently in Poland, working as a TV pundit covering the World Cup after failing to win selection for the tournament.

His current deal is under the salary cap, with Milos Ninkovic and Bobo both recently extending their marquee contracts for a further season under new coach Steve Corica.

That limits the club's capacity to improve Mierzejewski's wage, given he is already believed to be the highest-paid non-marquee player in the competition.