World champions Australia will slip from the top of the International Cricket Council one-day rankings for the first time if they lose their current series in New Zealand.
Australia, who lost the first match in the three-match series by 10 wickets in Wellington on Friday, have been top of the table since it was introduced in October, 2002.
In a statement on Friday the ICC said the Australians would be relegated to second place behind South Africa if they lose in New Zealand.
Australia lost the tri-series final to England this month while South Africa defeated Pakistan after beating India.
Australia's loss on Friday is their first by 10 wickets in 646 one-day internationals.
