Australia's Slipper warns lineouts and scrums key against Springboks

Captain James Slipper warned on Friday that Australia must improve their lineouts and scrums if they want to ride the momentum of beating South Africa with another win over the world champions this weekend.

The Wallabies are chasing back-to-back victories for the first time this season and with the Rugby Championship wide open it would leave them in a strong position with two games to play against a misfiring All Blacks.

They currently sit level on nine points with Argentina after two wins from three, four points clear of New Zealand and five ahead of South Africa at the tournament's midway point.

"Argentina are proving they're a pretty tough team to beat... it goes to show you how tight this competition is," Slipper told reporters in Sydney ahead of Saturday's sold-out clash with the Springboks.

"We've got four of the best teams in the world going head-to-head week in, week out... we're obviously coming off a good result, but I guess because it's such a short competition, each win and each back-up win is crucial.

"Momentum is a big thing in sport and hopefully we gain a bit of momentum going into that clash (in Melbourne this month) with the All Blacks."

While Australia hung on to beat South Africa 25-17 in Adelaide last week, it took a huge defensive effort to do so.

It was one of their best performances this year, but they conceded 16 penalties and lost six lineouts on their own throw, which allowed the Springboks to build constant pressure.

"(Assistant coach) Dan (McKellar) had us training pretty hard on the lineout, it was a big part of our game that struggled last weekend," said Slipper, who will play his 121st Test, equalling Michael Hooper, who is on mental health leave, and former teammate Adam Ashley-Cooper.

"You've got