Attacker Mathew Leckie has been injured just a fortnight before the Socceroos' opening match at the Asian Cup.
Leckie was replaced with what appeared to be a hamstring problem early in the second half of Hertha's 3-1 loss at Bayer Leverkusen.
The 27-year-old's German club have yet to release any details about the injury.
Australia national team coach Graham Arnold will be hoping for a positive prognosis with the Socceroos' defence of their Asian Cup title kicking off against Jordan on January 6.
Leckie has scored twice in his past six league outings, his latest coming midweek with a low crisp finish in a 2-2 draw with Augsburg.
He has 59 caps to his credit and although his nine goals do not make him a prolific scorer in international soccer he is one of the first names on the Socceroos' team sheet.
With the Socceroos due to head into camp in Dubai later this month before a final hit-out against Oman, Leckie's injury is the latest setback for Arnold who was unable to select the injured Daniel Arzani in his 23-man squad.
The availability of key midfielder Aaron Mooy, who was named by Arnold despite a knee injury that his English Premier League club Huddersfield Town believe requires a recovery period of "six to eight weeks," is expected to be confirmed within the next 24 hours.
Tom Rogic appears to have overcome a knee problem with his Scottish Premier League Celtic even appealing to FFA to allow him to play in the Old Firm derby next weekend before he links up with the Socceroos, a request unlikely to be granted.
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