Wallabies win spoiled by horror injury to playmaker Quade Cooper

A ruptured Achilles tendon to Quade Cooper has soured Australia's Rugby Championship defeat of Argentina on Saturday and could put the veteran playmaker in doubt to feature at next year's World Cup.

Flyhalf Cooper suffered the injury when slipping over early in the second half of the Wallabies' 41-26 win and he can expect a lengthy period recovering from damage that typically needs at least nine months to heal.

It is another agonising blow for the 34-year-old, who grasped at his lower leg in pain and needed assistance in a slow exit from the game.

Cooper was hoping to cement first-choice status after missing the entire 2-1 home series loss to England, having injured a calf muscle during the warmups for the first Test in Perth.

A return to action in the middle of next year will leave little time for the 75-Test veteran to prove himself ahead of the Rugby World Cup in France, beginning in September.

It continues an escalation of injuries for the Wallabies, particularly in the backline, where coach Dave Rennie couldn't call on Samu Kerevi, Tom Banks and Andrew Kellaway in Mendoza, where the visitors fought back from a 19-10 halftime deficit.

"We've had a reasonable run of injuries, haven't we?" Rennie told journalists, before the extent of Cooper's injury was revealed.

"I thought we were far more clinical and I'm happy with how we finished. We've got more in us but I'm really happy with the character we showed after late changes and losing a key guy within the game.

"That's the thing about this group. They have a lot of character and courage and they stood up."

Australia also had to cope with the absence of talismanic captain Michael Hooper after the flanker pulled out of the game for mental health reasons one day out from the Test.