By Jonathan Agnew
BBC cricket correspondent
One-day cricket is such a fickle business and that's why some people say it should not determine a World Cup because the balance of power can swing very quickly.
Australia will still be favourites but their recent run of defeats is fascinating to reflect on and it's very good for this tournament that they've suffered this lapse.
They have some key issues to resolve.
Andrew Symonds will be injured when the tournament starts and they're going to miss him enormously - he's absolutely key to the balance of their side.
Symonds bowls medium pace and spin, and it looks likely that those sort of bowlers will prosper in the Caribbean.
He is also an explosive batsman and a brilliant fielder.
Shane Watson, ostensibly his replacement, is not a bad cricketer but did not play well against England at all and has some work to do.
Adam Gilchrist will also miss the start and the other massive issue is that Brett Lee - rated the sixth best bowler in one-day internationals - is out of the tournament.
AUSTRALIA: SEEDED 1
Australia have won the World Cup a record three times
Ricky Ponting, Adam Gilchrist and Glenn McGrath are all bidding to get onto the winner's podium for the third time
His replacement, Stuart Clark, was a surprising omission in the first place, but the inclusion of Shaun Tait could be dangerous and could tip the balance the other team's way in a tight match.
He is exciting but if it is going to be a low-scoring tournament, someone who flings the ball all over the place at a speed where the ball will come onto the bat has to be a risk.
I would still be quite cautious about him as a one-day selection.
There are problems all over the place - Matthew Hayden is also struggling to get over an injury and despite his wonderful 181 in Hamilton has not been at his best of late.
It is hard to go into a tournament as favourites anyway, and particularly when you have had a rocky ride like they have.
But let's not get too carried away. Ricky Ponting is a great motivator and has done great things for that side.
In Australia's favour is the fact that they have two minnow matches before facing South Africa in their group.
Given that South Africa will be second favourites for the tournament that's going to be a huge game.
If Australia win it, they will look a huge force again.