Japan suffered another blow to their 2010 World Cup qualifying hopes on Monday when key defender Yuji Nakazawa pulled out of this month's trip to Qatar.
The experienced centre-back withdrew from the Nov. 19 Doha clash after suffering a groin strain while playing for Yokohama F-Marinos in a J-League match at the weekend.
Nakazawa's injury is a major setback for under-fire Japan coach Takeshi Okada after first-choice goalkeeper Seigo Narazaki pulled out of the squad with an ankle injury.
Japan's stuttering World Cup qualifying campaign could be further hampered if Celtic midfielder Shunsuke Nakamura fails to recover from a knee injury in time for the Group A game.
''It's feeling better but from the MRI results they say it will take another week or two to heal properly,'' Nakamura told reporters. ''I should be able to go to Qatar.''
The 30-year-old has been linked with a return to former club Yokohama in part to cut down on the frequent long-haul flights to play for Japan.
Japan are currently second in Group A with four points from two games, while Australia have a maximum six points. Qatar also have four points but have played one match more.
The top two in the two five-team Asian groups qualify automatically for the 2010 World Cup in South Africa.
Okada, who guided Japan to their first World Cup finals in 1998, has come under fire during his second spell in charge after a less than convincing qualifying campaign.
Ticket sales for Japan games have continued to fall but Nakazawa insisted there was no cause for alarm despite the rash of injuries.
''I don't think there's any need to be pessimistic just because I'm not playing,'' he said. ''Hopefully the fans will get behind us like they have in the past.''
Japan play Syria in a warm-up in Kobe on Thursday before travelling to Doha.