Father of Socceroo Dario, Vidosic revealed the Roar had known of Postecoglou's likely defection to Melbourne Victory for almost two weeks.

Many at the club believe Vidosic to be the perfect man for the job having been with them since the inaugural A-League season and credited with a vital role in the much-vaunted style of the Roar over their title-winning seasons.

"I have been through a lot with the club," Vidosic told reporters. "The last two years have been fantastic. From the performances, the results, to getting new owners. It is a really exciting time ahead of us."

Vidosic said Postecoglou told the coaching staff and players of his imminent departure after the Roar had made the grand final with their defeat of Central Coast.

There will be little time for preparation with the Roar still scheduled for two AFC Champions League matches, including a trip to FC Tokyo on Wednesday.

With only two draws from their opening four games, the Roar need to win both their remaining matches to stand any chance of progressing from Group F.

With a busy week and little time for a proper handover, Vidosic said he would be reticent to make any major changes for the Tokyo match with the aim still to transfer their domestic success to Asia.

"I don't need to make any changes," he said. "This group of players has been fantastic for us.

"I don't think any other club has had such a great playing group. As a matter of fact, we need to sit down and tie them down for a few more years."

After seven seasons at the club Vidosic believed he was the right man to guide the club into a new era given he had an intimate knowledge of the squad, but admitted replicating Postecoglou's leadership qualities would be the biggest challenge.