McKay, who captained the Roar to the A-League championship and premiership last term, is set for a move to Scottish giants Rangers, provided he obtains a UK work permit.

Should the Socceroo complete his move he'd follow Jean Carlos Solorzano and Kosta Barbarouses out of the championship-winning side, but Postecoglou is confident they can all be replaced.

"We've definitely laid some really good foundations. I don't see any reason why we can't be stronger than we were last year," Postecoglou told The Courier Mail.

Postecoglou explained he had successfully handled a player overhaul at the club in the past which boded well for the team who will compete in next year's AFC Champions League.

He added: "The biggest challenge we had was last year when we tore back the whole club in terms of the footballing side.

"We changed players, we changed staff, we changed everything - that was a challenge because if we didn't get it right then we would have been in a pretty disastrous situation.”

Postecoglou has already added attacker Kofi Danning along with defenders Jack Hingert and Matthew Jurman this off-season, while Bahrain international Sayed Mohamed Adnan appears set to join the club too.

However, the Roar haven't added to their midfield stocks and with McKay likely to depart, they may have a problem but Postecoglou said players already at the club could help the team improve.

"Massimo Murdocca didn't really have much of an influence last year. He's an important player for us," Postecoglou said.

"Lukey Brattan will have an opportunity to step up, and with Thomas Broich, I expect him to play better this year than he did last year because for any foreigner coming in, the first year's the most difficult year."

Brisbane begin the 2011-12 campaign at home to Central Coast Mariners on October 8.