Michael Cheika forecasts changes ahead of Springboks test

Wallabies coach Michael Cheika has forecast changes to his back-row despite the team notching its first win of the Rugby Championship.

The Australians overcame a slow start to deliver an impressive second half in Canberra that included five tries to outscore Argentina 45-20.

Cheika wasn't particularly happy with the first-half efforts of his back-row of skipper Michael Hooper and Ned Hanigan and No.8 Sean McMahon, who were outplayed by the Pumas.

But he felt a lift in their intensity and urgency in the second half was key to the Wallabies revival, with the victory coming after last week's disappointing draw with South Africa.

Ahead of the return clash with the Springboks in a fortnight in Bloemfontein, Cheika said he had some changes in mind.

"I think that's been a good balance but it's the competition for the spots," Cheika said.

"There's a couple of other chaps brewing in the background that we are looking to get a game in the back-row."

Those players include Reds duo Adam Korczyk and Lukhan Tui, who usually plays lock, while he was impressed with the contribution from Waratahs flanker Jack Dempsey off the bench against the Pumas.

Cheika said he'd been happy with what 22-year-old Hanigan had offered in his six Tests this year, particularly given he'd only played three Super Rugby games before his surprise call-up.

While's Hanigan's defence and set-piece work is strong, his clean-out goes missing at times, with fatigue after a big year a possible factor.

"There's a mental load when you're coming from nowhere and Hanigan, Izack Rodda and Jordan Uelese who weren't starting in Super Rugby at the start of the year so it's about trying to get that right balance," Cheika said.