LONDON • Australia coach Michael Cheika may be the new boy among the major rugby players but he has proved that he learns fast.

The Wallabies have won the Southern Hemisphere's Rugby Championship and reached the Rugby World Cup semi-finals in less than a year. On Sunday, fly-half Bernard Foley's last-minute penalty saw Australia to a 35-34 win over Scotland.

Cheika's men now face Argentina on Sunday, with defending champions New Zealand taking on South Africa in the other last-four clash a day earlier.

With no Northern Hemisphere team in the last four for the first time in Cup history, the tournament now becomes a repeat of the Rugby Championship, which was shortened this year to make room in the calendar for the World Cup.

"It does mean everyone knows each other very well," said Cheika, thrust into the job of Australia coach last year after the resignation of former boss Ewen McKenzie.

"I am the junior member of the Rugby Championship. The other coaches, Daniel Hourcade (Argentina), Steve Hansen (New Zealand) and Heyneke Meyer (South Africa) have all got more experience than me. But we will prepare as best we can and put a performance together on Sunday."

The Wallabies beat the Pumas 34-9 in Mendoza in July. But Argentina served notice of their quality with a convincing 40-23 quarter-final win over Six Nations champions Ireland in Cardiff on Sunday.

"They've improved a lot," said Wallaby wing Adam Ashley-Cooper, 31, of Argentina. "They have the ability to tackle all over the field now. We know they've got a dominant forward pack. They've got a great set piece and now they've got outstanding backs.

"They're a threat from one to 15 so we're going to have to look very closely at their game and formulate a strategy that we think will beat theirs."

AGENCE FRANCE-PRESSE