Wallabies skipper Stirling Mortlock has been ruled out of the opening Bledisloe Cup and Tri-Nations Test against New Zealand in Sydney on Saturday.

Mortlock has failed to recover sufficiently from the head knock he sustained in the second half of last weekend's Tri-Nations Test match against South Africa.

His departure led to flank George Smith assuming the captaincy.

Smith will continue in that role at ANZ Stadium, according to an Australian Rugby Union (ARU) media release.

"Stirling was concussed last weekend," revealed Aussie coach Robbie Deans.

"We had hoped that, with time, the symptoms would resolve themselves, but that hasn't happened soon enough for this match, so we've made the call early," Deans said on Tuesday.

"George [Smith] took over once Stirling left the field in Perth and got the team over the finish line so we've opted to maintain continuity by leaving him in charge."

The Wallabies team for Saturday's match will be announced at a public function in Martin Place, Sydney, at 13.30 local time (03.30 GMT) on Wednesday.

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