Australia captain George Gregan will miss the rest of the Super 12 season after breaking his leg in the ACT Brumbies loss to New South Wales on Saturday.
Gregan limped off the ground after colliding with NSW scrumhalf Chris Whitaker and x-rays later revealed that he had suffered a small fracture below the left knee.
The injury is expected to sideline Gregan for up to six weeks. There are four rounds to go in the regular Super 12 competition followed by two weeks of finals.
Australia's first test of the international season is against Samoa on June 11.