South Africa will showcase their young backline talent while Argentina need an 80-minute performance as both teams attempt to keep their Rugby Championship title hopes alive on Saturday.

Shaken by a 24-17 loss at New Zealand's Eden Park fortress last week, a much-changed Springboks are desperate to respond in their rematch in Wellington.

Argentina also need to bounce back in Sydney after a 28-24 loss to Australia in Townsville, where the Wallabies conjured a winning try well after the final hooter.

The results left New Zealand top of the standings at the midway point of the annual southern hemisphere tournament, a bonus point ahead of Australia, with both having won two games from three.

Defending champions South Africa and Argentina are both one win from three and could drop out of contention if beaten again this week.

- Springboks overhaul -

Coach Rassie Erasmus has discarded a host of established players who formed the core of South Africa's World Cup triumphs in 2019 and 2023, making seven starting changes.

Gone from the backline are Willie le Roux, Jesse Kriel, Damien de Allende and Handre Pollard as Erasmus turns to a more dynamic group, spearheaded by 23-year-old playmaker Sacha Feinberg-Mngomezulu.

Damian Willemse and Canan Moodie combine in an unpredictable midfield while wing Ethan Hooker makes his starting debut.

Some commentators have dubbed it a high-risk, high-reward selection ploy from Erasmus two years out from the next World Cup.

New Zealand have made five changes, including the selection of former sevens star Leroy Carter, who becomes the ninth player to make his debut this year for the rebuilding All Blacks.

Both sides are hinting at a more expansive approach after the Auckland Test was dominated by physical confrontation and box kicking.

Erasmus expects a better quality match.

"I think we were really bad last week but I don't think they were outstanding either," Erasmus said of the All Blacks.

"It was an error-ridden game. There was a hell of a lot of intensity and that's what you need in Test match rugby, but I don't think either team played really, really well.

"They were better than us, that's the bottom line."

South Africa will reclaim the number one world ranking off New Zealand if victorious.

- Pumas 'reset' -

Australia were rewarded in Townsville by their late decision to chase a match-winning try rather than settle for a draw by kicking a penalty goal.

Prop Angus Bell's 85th-minute score stung the Pumas but coach Felipe Contepomi said they had moved on quickly.

"We try to always reset to zero at the start of the week, no matter the result that came before," he said.

Added motivation for Argentina is veteran hooker Julian Montoya's 50th Test as captain, one short of the national record.

Contepomi sprung a major surprise by naming Joaquin Oviedo in his back row, dropping the inspirational Pablo Matera to the bench in one of three starting changes.

Wallabies coach Joe Schmidt has handed Tane Edmed a first Test start in place of the injured Tom Lynagh.

Schmidt said the 25-year-old Edmed had already proved he is a Test-level player after coming off the replacements bench early in last month's narrow loss to the Springboks in Cape Town.

"Tane, he was super in that game. For a patched-together backline, I thought he filled in really well. That would have contributed a little bit to his confidence," said Schmidt.

"We wanted to give him more confidence and more time to familiarise himself with running the team in a pivotal position like number 10."