Promoting Will Genia to the captaincy for Friday night's Rugby World Cup encounter with the USA was a selection no-brainer for Wallabies coach Robbie Deans.

The 23-year-old halfback will become Australia's 78th Test captain after regular skipper James Horwill was given a week off to recover from a shoulder niggle.

The elevation continues Genia's meteoric rise from the Queensland Reds' bench in Super Rugby little more than two years ago to arguably the world's premier No.9 and now captain of his country.

"Obviously, I'm very, very happy and proud with the fact that I get to lead the group, but it's not about me - it's about the team and that's always been my focus," Genia said on Wednesday.

"Whether I've been lucky enough to lead the Reds or whatever, it's always been about the team.

"I just want to get out there and play and rectify a lot of the things that we didn't do well last week (against Ireland).

"Everyone's disappointed with last week and we want to make things right."

Genia said his no-fuss coach advised him of the decision on Monday.

"It was just as simple as: 'Mate, we'd like you to lead the group'. That's all it was, a simple conversation," Genia said.

Australia's little general will be the 13th player to captain the Wallabies at a World Cup - and seventh Queenslander after Horwill, John Eales, Michael Lynagh, Jason Little, Rod McCall and Andrew Slack.

"Willie's ready for the responsibility," Deans said.

"He's got a lot of background in leadership; he leads in games, he's part of the leadership group, so it was pretty straightforward."

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