SYDNEY (AFP) - Wallabies captain Stirling Mortlock will miss this weekend's Tri-Nations Test against New Zealand after failing to recover from a head knock against South Africa, coach Robbie Deans said Tuesday.

Mortlock left the field looking dazed in the second half of the Wallabies' upset 16-9 win over the world champions in Perth and Deans said he was not fit to play in Saturday's blockbuster against the All Blacks in Sydney.

"Stirling was concussed last weekend. 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.

The coach named flanker George Smith, who took the captain's armband for the latter stages of the Springboks match, as stand-in skipper against New Zealand.

"George 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," he said.

The Wallabies team for Saturday's Tri-Nations Test, which also doubles as the opening match of the trans-Tasman Bledisloe Cup, will be named Wednesday.

Mortlock's absence is a major blow for Deans as he leads the Wallabies into their first clash against his native New Zealand since he took over as coach late last year.

Mortlock was inspirational while on the field against the Springboks, claiming one of Australia's two tries after muscling past three defenders.

Rugby league convert Ryan Cross, who has been on the bench for the Wallabies' four Tests this year, is expected to replace Mortlock and make his run-on debut.

Meanwhile, Australian centre Berrick Barnes took delight in rubbing salt into the wounds of kiwi fans still smarting over New Zealand officials' decision to reappoint Graham Henry as All Blacks coach, allowing Australia to poach Deans.

Barnes revealed his teammates had given Deans a uniquely Australian nickname to emphasise the coach's his new allegiance to the All Blacks' arch-rivals.

"He's got a lot of Aussie in him now. I think the best nickname is 'Dingo'. It's good isn't it?" Barnes said.