Postecoglou controversially walked out on the national team in November after Australia had secured its passage to Russia.

Since he left his job the 52-year-old, who reportedly maintained a distance between himself and his players while in charge for four years, has fired the occasional broadside at the playing style that new coach Bert van Marwijk has implemented and at squad selections for the World Cup.

Postecoglou told the BBC recently that he would be watching the tournament "with a beer on a Greek island".

Cahill said today that the Yokohama F. Marinos coach has touched base with him and Mile Jedinak before Australia takes on France, while Mark Milligan said he hadn't heard from Postecoglou.

"It's bittersweet and a bit sad for Ange not to be here," said Cahill, 38.

"I actually got a text from him the other day and so did Mile. He's played a massive part in this. He's just passed the baton on to Bert and his staff. We're going to try and do the best we can for our country in these coming weeks.

"The good thing under Ange was that we dominated games in a unique way. Ange played a massive part in where we are today."

Van Marwijk has changed Australia's playing style to a more defensive-minded, counter-attacking approach compared to Postecoglou's possession-based offensive mantra.

Cahill admits the change is not surprising and completely normal in football.

"When you have a new coach and set-up it's a short space to time," he said.

"We have to win, so there's no choice. We have to try and get through our group.

"We need the results and he's definitely shown us with the style that he wants us to play, but at the same time we're trying to find the levels between football, pressing and making sure we don't get caught out by France on Saturday."