It is not only this series that hangs in the balance tonight. This Australian side's claim to be one of the greatest teams in cricket history will be difficult to sustain if they are defeated by New Zealand tomorrow. Lawrence Booth's mathematical analysis confirms the significance of such a defeat, which would put South Africa on top of the ICC World Championship table. Having said that, great teams are those that quickly return from setbacks and the numbers could change soon enough.

Australia might even win in Perth, though that now looks highly unlikely. It might be a little harsh to say Australia's claims to greatness will be demolished should their batting crumble to Daniel Vettori on the driest WACA pitch for years.

After all Australia had by far the better of the Kiwis in the first two matches and will now be rueing the role rain played in those matches. In addition, this would be Australia's first poor performance for more than two years, since the rain-affected draw in Galle in September 1999, a match they looked likely to lose before another of the seaside city's regular downpours swept over the Dutch Fort and saved an Australian side who were distinctly second-best.

Yes, the famous loss in Calcutta ended Australia's world-record winning streak and let India into a series they eventually won. But Australia had been in an apparently impregnable position at the halfway point of that match, and only lost narrowly in the next match in Chennai. In the conditions these can hardly be said to be poor performances. Ditto for the declaration match at Headingley a few months back, which Australia dominated for four days.

In Perth, however, the Australians have been outplayed throughout by a New Zealand team revealing fresh talent and, under the proactive leadership of Stephen Fleming, commendable spirit.

The first thing Fleming should call for if his side wins this match is an explanation from his selectors. While whispers about changing the Australian XI are already being heard, a more pertinent question to ask is why the Kiwi selectors chose the leaden-footed Matthew Bell for two Tests ahead of the obviously gifted Lou Vincent? And how come the lively pace duo of Shane Bond and Chris Martin were mere reserves a couple of weeks ago?

Mark Ray has covered Australian cricket since 1987 and is also the author of a number of books on the game.

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