London - Scotland will have to succeed where England and Wales failed and break the Australian defence in their World Cup quarter-final on Sunday, the Scots' Australia-born resource coach Nathan Hines.
The 39-year-old -- who was born in Wagga Wagga but qualified for Scotland through a Glasgow-born grandfather -- said that if Michael Cheika had not taken over as Australia coach one year ago, the Wallabies would not be contenders for a record third World Cup.
However, Hines, the first Scotland player to be sent off in a Test match for throwing a punch in 2002 against the United States, has been impressed by the way the Wallabies held out against Wales in their final Pool A game despite having two players in the sin-bin.
"They have a very solid line and their players defend like dogs," said Hines on Tuesday.
"England (hammered 33-13) and Wales (who lost 15-6) couldn't find a way through it."
Hines, capped 77 times by Scotland from between 2000 and 2011, said Cheika's powers of motivation had played a crucial role in turning the team
Hines played under Cheika for Irish province Leinster, whom the Australian had turned from under-achievers into European Cup winners.
"'Cheiks' is good at getting a team motivated, making a team think that he is right behind them, which his is," said Hines.
"He's done a good job with Australia. Two years ago they wouldn't be coming into this World Cup as strong as they have."
Hines, who had two spells in France with Perpignan and then Clermont, said another factor in Australia's marked improvement was Cheika's decision to bring in Argentinian hooker Mario Ledesma as scrum coach.
The Australians totally dominated the scrum in their key win over England.