An official announcement appears imminent with the Polish-born, Hobart-raised raised 28 year-old returning to Australia for the first time to play since departing to join Leicester City as a teenager in 2005.
Released recently after two seasons with Leyton Orient, who have been relegated from the Football League, Cisak never made a senior appearance for the Foxes.
But has had spells with no less than seven clubs throughout English football's lower tiers, and was called up by Socceroos coach Ange Postecoglou in 2015.
Arnold was forced to dip into the market to bolster his goalkeeping stocks after the sudden and unexpected exit of Danny Vukovic to Genk.
Cisak' arrival will lay down the gauntlet to Redmayne, who did himself no harm earlier this month with an eye-catching display for the A-League champions in their friendly defeat to EPL giant Arsenal.
Arnold has also found a replacement for former marquee Filip Holokso, with an as yet unnamed right winger from Poland understood to be on his way to Australia to fill the void left by the Slovakian.
