Len Ikitau and Marika Koroibete scored two tries apiece as Australia secured a second successive victory over world champions South Africa in the Rugby Championship in Brisbane.

Ikitau touched down twice in the first half, although the Springboks took the lead through centre Lukhanyo Am two minutes into the second half.

Koroibete struck twice in six minutes to seal a bonus-point Australia win.

New Zealand reclaimed top spot in the world rankings after beating Argentina.

The All Blacks are now 10 points clear in the Rugby Championship table having won all four of their games while Australia move up to third, one point behind South Africa.

New Zealand's win saw them leapfrog the Springboks into top spot prior to their meeting in Townsville next week.

"We were really beaten," said South Africa coach Jacques Nienaber.

"We got hands down beaten in everything - defence, kicking game, attack. This isn't a performance that was worthy enough for a Springboks performance."

Soon after South Africa scrum-half Faf de Klerk was shown a yellow card for slowing the ball in a ruck, Ikitau sprinted past two defenders to score the opening try.

Ikitau crossed for a second time in the 21st minute following Koroibete's off-load, before De Klerk's return rejuvenated the Springboks as they trimmed the deficit to three points by half-time.

With Wallabies flanker Lachie Swinton yellow-carded for a high tackle on Duane Vermeulen, the visitors quickly snatched the lead after the restart when Am touched down.

However, Australia regained the initiative thanks to winger Koroibete, whose first try was created by Taniela Tupou's audacious no-look pass.

Koroibete's second established a 13-point lead and Australia defended it stoutly, repelling waves of South African attacks in the closing stages to see out a victory - seven days after their dramatic 28-26 win in Brisbane.

All Blacks too strong for Argentina

In addition to leapfrogging South Africa in the rankings, New Zealand closed in on their 18th title with a 36-13 bonus-point success over an improved Argentina in the second of Saturday's double-header at Suncorp Stadium.

Despite coach Ian Foster having made 11 changes from last week's 39-0 win over the Pumas, the All Blacks were too strong for the South Americans with tries from Patrick Tuipulotu, TJ Perenara, Tupou Vaa'i (2) and Samisoni Taukei'aho enough to secure another dominant victory.

South Africa must defeat New Zealand twice and pile on the tries in their last two matches to earn bonus points and have any hope of stealing the silverware away from the All Blacks.
Teams

Australia: Banks, Kellaway, Ikitau, Kerevi, Koroibete, Cooper, White, Slipper, Fainga'a, Tupou, Rodda, Philip, Swinton, Hooper, Valetini.

Replacements: Kaitu'u, Bell, Robertson, Swain, Samu, McDermott, Hodge, Petaia.

South Africa: Le Roux, Nkosi, Am, De Allende, Mapimpi, Pollard, De Klerk, Nyakane, Mbonambi, Malherbe, Etzebeth, Orie, Kolisi, Mostert, Vermeulen.

Replacements: Marx, Kitshoff, Koch, Van Staden, Smith, Wiese, Jantjies, Willemse.

Argentina: Mallia, Cordero, Cinti, Chocobares, Boffelli, Carreras, Bertranou, Gigena, Montoya, Medrano, Alemanno, Lavanini, Gonzalez, Kremer, Matera.

Replacements: Socino, Muzzio, Pieretto, Petti, Lezana, Garcia, Miotti, Moroni.

New Zealand: J Barrett, Jordan, Ioane, Tupaea, Bridge, McKenzie, Perenara, Moody, Taukei'aho, Lomax, Tuipulotu, Vaa'i, Blackadder, Savea, Sotutu.

Replacements: Taylor, Bower, Tuungafasi, Barrett, Jacobson, Christie, B Barrett, Ennor.