Michael Cheika's Australia have got over the shock of almost tumbling out of the World Cup and say they are ready to end Argentina's impressive run to the semi-finals on Sunday.

But the Twickenham clash has been given added punch by the rise of the new Southern Hemisphere rugby power under Daniel Hourcade who is determined to give the two-time World Cup champions a hard time.

The Pumas have beaten Australia and South Africa in the past year and crushed Ireland 43-20 in the quarter-final with their free-flowing rugby.

Cheika was forced on the defensive however after Australia needed a wrongly-given last-minute penalty to beat Scotland 35-34 in their quarter-final last weekend.

The coach blamed himself for not having the Wallabies in the right mental state to confront Scotland. But he insisted that has changed.

"Their heads are in a good state," said Cheika.

Argentina, who also reached the semi-finals in 2007, will also face a scrum which has a coach, Mario Ledesma, who knows the Pumas intimately. The former hooker only retired after the 2011 World Cup.

Cheika, who has just celebrated the anniversary of his taking over from the troubled reign of Ewen McKenzie, said Ledesma's patriotism will not distract him from the task in hand.

"It’s interesting because we’re up against his country of birth he’s played passionately for," said Cheika, whose predecessor McKenzie's end was precipitated by a rare reverse against the Pumas in October last year.

- Folau's return -

"You go into battle against those guys that you played with for many years and I think it inspires you to do better."

The Wallabies have been boosted for their sixth semi-final by the return of star fullback Israel Folau and No 8 David Pocock -- who have recovered from ankle and calf injuries respectively. They are however without first choice prop Scott Sio because of an elbow injury.

Pocock's backrow partner Michael Hooper will win his 50th cap just short of his 24th birthday and he knows they will have to overcome a formidable Argentina side.

"We are looking forward to the Argentinian challenge and also guessing what they will bring to the party," said Hooper.

"Not least what their back row will do in varying their tactics."

Wallaby skipper Stephen Moore can see no quarter being given all over the pitch.

"As a front rower the set piece, the scrum, the lineout and the driving maul will be huge weapons to counter," the 32-year-old told AFP.

"But they have developed a very attacking game, lots of flair and with a strong back three who are very creative and keen to get their hands on the ball, it is now a big part of their game."

Central to Argentinian hopes of making history and reaching the final will be fly-half Nicolas Sanchez and experienced centre Juan Martin Hernandez, whose artistry has earned him the nickname of 'The Magician'.

Sanchez, who goes into the weekend second on the points list at the tournament with 74, five adrift of Scotland's Greig Laidlaw, says having Hernandez beside him is a real boon.

"Juan is a hero in the team, he means a lot to the team, he's a great leader for us," said Sanchez, who turns 27 on Monday.

"He's a second fly-half as well, playing from 12, so he simplifies a lot of the things we have to do.

"And that is a great help to me."

Pumas coach Hourcade, who like Cheika has bonded together a squad he found riven apart when he replaced Santiago Phelan in October 2013, believes their peak is still some way off.     

"We should have a powerful team within two years," said the 57-year-old anticipating the benefits of more Rugby Championship and Super Rugby in the Southern Hemisphere.

"When Julian Montoya, Lucas Noguera, Paul Matera, Thomas Lavanini have 30 games per year, and win against strong teams, you'll have powerful guys.

"Of course we aim to go as far as much as possible in this World Cup, but the goal we have set is 2019."
Source: AFP