Wallabies inside centre Pat McCabe and winger Digby Ioane have both been ruled out of the remaining Test matches against the British and Irish Lions due to injury.
Both players were injured playing the first Test match in Brisbane on Saturday and both will require further examination by specialists.
In a further blow for the Wallabies fullback Berrick Barnes has been ruled out of the second Test match after he was concussed in the first half.
Under IRB guidelines Barnes may not be considered for selection but the Wallabies are hoping that he will have recovered in time for the third Test in Sydney.
Brumbies back McCabe re-injured his neck in the first Test in a similar place to the injury he sustained in the Wallabies end of year tour and he will see a specialist in Sydney this week to determine whether the injury rules him out for the Super Rugby play offs.
Reds winger Ioane suffered internal damage to his right shoulder and will also need to see a specialist and surgery is a possible scenario.
The Wallabies did get some good news on the medical front as inside centre Christian Leali'ifano and fellow centre Adam Ashley-Cooper are making good progress and could be available for selection this weekend.
Leali'ifano suffered concussion in the opening minute of the first Test and his progress is also being monitored with IRB guidelines ahered to.