Australia booked a World Cup quarter-final clash with either England or Tonga after cruising to a 55-12 bonus-point victory over Fiji.

Matt Giteau was the star of the show and celebrated his 50th Test cap by scoring two of Australia's seven tries in a personal haul of 27 points.

The Wallabies enjoyed a mountain of possession and rarely needed to get above second gear as they worked a hat-trick for Drew Mitchell and tries each for Adam Ashley-Cooper and Stephen Hoiles.