The Roar coach says he is treating every match from now on like a cup final, as his side prepares to take on Melbourne Heart at Suncorp Stadium on Sunday.

Brisbane, who are currently seventh on the A-League ladder, can guarantee themselves finals football by winning both their remaining games, against Heart and Sydney FC.

While the defending champions could still qualify with less than six points, depending on other results, Mulvey says his players will be going for the win on Sunday.

"The way I'm looking at things right now is the season is actually over," Mulvey said. "We're in cup final mode now.

"The regular fixtures are over and we're into the situation where we're playing cup finals every week."

Roar have the advantage of playing their final two regular season games at home, and Mulvey called on fans to come out in force to give the team an extra edge.

"What I'm saying to everybody in Brisbane right now is get out on Sunday and watch us play, because this is a massive game," Mulvey said.

"Something that Brisbane have been good at in the past is playing finals football, and it's starting a couple of weeks early.

"We're approaching the game as if it's a must-win situation. We're really looking forward to it, and I encourage all the fans in Brisbane to come out and watch us play."

With veteran centre-back Jade North called into Socceroos camp ahead of the World Cup qualifier against Oman in Sydney on Tuesday, Mulvey will be forced to make changes to what has been a settled starting XI in recent weeks.

The coach remained coy about whether he would entrust an out-of-favour Matthew Jurman to fill in for North, or move one of his wide players, Shane Stefanutto or Ivan Franjic, into the role, ahead of a closed training session on Friday morning.

"There's still a couple more sleeps to go so there's plenty of thinking to be done, but I know what's going to happen," Mulvey said.

Though the loss of North comes at a critical point of the season, Mulvey admitted it was bad timing but said his side were not the only ones to lose a key player.

He added: "If you look across the A-League this weekend, there's lots of people having to make shuffles, so we're not an exception in that regard."