David Pocock faces an anxious wait for medical results on his injured left knee after the flanker hobbled off the field after only 14 minutes of the ACT Brumbies' Super Rugby match against the New South Wales Waratahs on Saturday.
FOX Sports reported that Pocock, who watched the remainder of the all Australian clash sat pitchside with ice packs strapped to his knee, had suffered a suspected anterior cruciate ligament injury.
Australia coach Robbie Deans was watching on from the stands and will be hopeful that the 24-year-old Pocock, arguably the best flanker in world rugby, has not suffered such a significant injury with three tests against the British and Irish Lions in June and July.
The skilful poacher was driven off a ruck by Wallabies team mate Adam Ashley Cooper and fell backwards on the ground where he laid as play continued before the Brumbies medical team helped him off the field.
He was replaced by former Wallabies skipper George Smith, who made his first appearance since returning from playing in Japan.
Pocock missed the majority of Australia's November tour to Europe after undergoing knee surgery to rectify an issue suffered in an August defeat by the All Blacks in Sydney.
(Reporting by Patrick Johnston in Singapore; editing by Amlan Chakraborty)