Coach Ange Postecoglou of the Roar watches on during the round 11 A-League match between the Brisbane Roar and the Central Coast Mariners at Suncorp Stadium on December 17, 2011 in Brisbane, Australia.

Coach Ange Postecoglou of the Roar watches on during the round 11 A-League match between the Brisbane Roar and the Central Coast Mariners at Suncorp Stadium on December 17, 2011 in Brisbane, Australia. Photo: Getty Images

At a public reception honouring Brisbane's second straight A-League title yesterday, in-demand coach Ange Postecoglou gave anxious Roar owners a glimmer of hope by telling fans: ''let's make it three''.

But when the triumphant team returned to their training ground, Postecoglou broke the ''tough and emotional'' news to his players that he was leaving.

Assistant Rado Vidosic is expected to take over the Roar reins today after four-time championship winning coach Postecoglou opted for a new challenge.

He is set to be named as the Melbourne Victory's new coach in the next few days.

Postecoglou was all smiles at a tickertape parade and reception held in Brisbane's CBD celebrating the Roar's back-to-back A-League championships.

But he cut a more sombre figure barely an hour later when he revealed a decision to his players he had privately made ''a month or so'' ago.

''I just felt it was the right time to tell them all my time at the Brisbane Roar has ended - it was a tough and emotional afternoon,'' Postecoglou said.

But Postecoglou admitted he almost changed his mind as the Roar juggernaut showed no sign of slowing down.

''You can't walk away from something that you have invested so much time and energy into - I didn't make it lightly,'' he said.

''We have been through a lot together, enjoyed success and formed a close bond - it was not an easy thing to do [walk away].''

His resignation ensures he will not be involved in the Roar's two final Asian Champions League group games, starting next Tuesday in Japan against FC Tokyo.

Postecoglou almost walked away a year ago but said ''it didn't feel right'' with the Roar facing an uncertain future under Football Federation Australia ownership.

A year later the Roar is the envy of the A-League under new owners Bakrie Group who reportedly offered Postecoglou a $6 million, four-year deal to stay.

''To be honest it was never about the money - it was about a new challenge,'' Postecoglou said.

''A lot of people see job security as the No.1 priority and I had it here - maybe that's what was bugging me.

''I kind of need something to keep me going.''

Fans did their darndest to persuade Postecoglou to stay, chanting ''one more year'' as he left the stage. But it wasn't to be. AAP