The Socceroos have been dealt a body blow on the eve of their World Cup qualifiers with Honduras, with Tim Cahill limping off while playing for A-League club Melbourne City.
Cahill was a surprise name on City's team sheet for Friday night's clash with Sydney FC, making his first start of the season.
Looking to build on his side's strong start to the new campaign, City coach Warren Joyce included the 37-year-old against the A-League title-holders.
But City's gain might have turned into Australian football's pain after 15 minutes. Cahill landed awkwardly as he attempted to hurdle Sydney FC's Jordi Buijs after a challenge, requiring treatment on his right ankle.
Five minutes later, he collapsed on the pitch, signalling to the City bench that his night was over.
It was reported Cahill had told City substitute goalkeeper Dean Bouzanis he "tweaked his ankle."
Cahill cast a forlorn figure as he left the field, with one broadcaster describing him as "devastated."
The Socceroos' record scorer netted a double to ensure Australia defeated Syria in last month's Asian playoff battle.
Cahill was due to fly to Central America on the weekend to link up with coach Ange Postecoglou's squad in San Pedro Sula.
The away leg takes place on Nov. 10 before the return match on Nov. 15 in Sydney.