Cahill, 35, played a full match for Shanghai Shenhua in a 1-0 win at home to Tianjin Teda on Sunday but will not travel to Europe to link up with the national team, instead remaining at his Chinese Super League club to undergo treatment on an Achilles tendon issue.
Luzern's Oliver Bozanic, who played at the 2014 World Cup but was overlooked for the Asian Cup by head coach Ange Postecoglou, replaces the veteran forward.
"Unfortunately won't be travelling to meet the national team. Want to wish the staff and team all the very best," Cahill tweeted.
Western Sydney Wanderers defender Spiranovic has also been forced to pull out, prompting Bailey Wright of Preston North End to be selected.
Australia play world champions Germany in Kaiserslautern on Wednesday, followed by a game against Macedonia in Skopje.
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