Galatasaray forward Harry Kewell has emerged as an injury doubt for the World Cup just days before Australia coach Pim Verbeek names his preliminary squad.
Kewell is reported to have re-injured the groin which he had surgery on in January and is set to miss Gala's final two games of the Turkish season.
The 31-year-old former Leeds and Liverpool man had only just returned after four months on the sidelines, but just two days after his comeback broke down again - casting a major doubt over his participation in South Africa.
"Right now, I think it's going to be very difficult," said Galatasaray assistant coach Johan Neeskens.
"Stage by stage he got better but then he fell back again. He chose to stop training and take treatment. But sometimes after three or four days, if he stops treatment and starts training again, it comes back again.
"He started again with the team a week ago but now in the second week he got some pain and didn't feel comfortable. On Tuesday, he stopped again and couldn't continue the work because it's too painful.
"I don't know if he really is going to make the World Cup at this rate. First of all it's up to himself and the doctors in Australia. If he cannot participate, it's a big loss for Australia."
Verbeek will name a 30-man preliminary squad on Tuesday with a final 23-man group to be revealed on June 1.
Kewell is expected to be included in the initial party, but his latest injury setback may mean Verbeek will have to leave him out of the final squad.
Australia have been drawn in Group D alongside Germany, Serbia and Ghana and will step up preparations against New Zealand in Melbourne on May 24.
Verbeek's side will also face Denmark and the United States in Roodepoort at the start of June before their World Cup opener against Germany in Durban on June 13.