Foot injuries have ruled midfielder Massimo Luongo and goalkeeper Mitch Langerak out of the November 15 crunch clash in Bangkok, with first-choice striker Tomi Juric also in heavy doubt due to a knee problem.
Brattan has been called up to replace Luongo after being cut from coach Ange Postecoglou’s extended 30-man squad last week while Swansea City gloveman Mark Birighitti will step in for Langerak.
In another more considerable blow, Juric limped off the field eight minutes into his match for Swiss outfit FC Luzern overnight with suspected knee ligament damage.
The 25-year-old is awaiting scan results, but dropped China-based marksman Apo Giannou has been placed on standby.
Should he be ruled out, Postecoglou will have decisions to make regarding the composition of his attack, having already made the big call to leave talisman Tim Cahill at home to recover from an Achilles injury.
While there are other options, in-form Maclaren appears the mos t likely to start on the back of his two goals from as many games for the Roar.