The 27-year old Australian international has recently been linked with Premier League returnees Crystal Palace, Championship club QPR and UAE side Baniyas but is highly unlikely to depart the Victory for whom he starred in a defensive midfield role last season.
"We haven't received an official offer for him and, to be honest, if we did we're not going to let him go," Postecoglou told the Herald Sun.
"He's contracted for another two years, he's a very valuable member of our football club and that's the reason why we brought him here.
"We don't really need the transfer money, we're not looking to make money.
"Ultimately our intention is, from a football perspective, to keep him at the football club."