Peter Betham replaces Henry Speight in Australia's Rugby Championship squad

Speight, who was born in Fiji, was included in the Wallabies' squad even though he does not become eligible for selection until September 11, almost a month after the tournament starts.

The winger picked up the injury during the Brumbies' 26-8 defeat to Warathahs in last Saturday's Super Rugby semi-final clash.

"It's disappointing for Henry but I've got no doubt that he'll go back and work hard during the rehab process to get his injury healed before he becomes eligible to play for Australia," Australia coach Ewen McKenzie said.

"On the flip side, we bring in a guy in Peter Betham who has had significant exposure to our program over the past year and who made his Test debut against New Zealand in 2013.

"He's a quality team member on and off the field and will be determined to make the most of the opportunity he has been given."

Betham, whose solitary cap came against New Zealand in Dunedin last October, has recently recovered from a broken foot.

Australia's Rugby Championship campaign starts with a double-header with world champions New Zealand, the first of which takes place in Sydney on August 16 the sides meet in Auckland a week later.