The Wallabies have equalled their lowest-ever position in the world rankings after losing to Ireland on Saturday.
Victory in Dublin strengthened Ireland's position in third with 0.64 of a point increase from 84.84 ratings points to 85.48. Australia drop to fifth, with their rating points tally decreasing from 84.22 to 83.59.
England, who ended a five-match losing streak on Saturday, move to fourth place by default as their 28-9 win over 11th-ranked Samoa had no impact on the rankings.
Another switch by default, sees Wales and France trade places in sixth and seventh – despite the Dragons suffering a 34-16 defeat to the All Blacks – because Argentina, who remain ninth, upset Les Bleus 18-13 in Paris.
Georgia ended Japan's 11-match winning streak with a 35-24 win in Tbilisi, bringing an end to the Brave Blossoms' stay in the top 10 as they now occupy 11th, with Samoa jumping to 10th.
Fiji's 20-14 win over the USA puts them in 12th at the expense of Tonga, who lost 37-12 to Scotland. The only other change in the top 20 sees Romania claim 17th spot, following their 18-9 victory over Canada.
World Rugby rankings:
1. New Zealand 93.70
2. South Africa 89.93
3. Ireland 85.48
4. England 84.21
5. Australia 83.59
6. Wales 79.94
7. France 79.66
8. Scotland 78.78
9. Argentina 78.23
10. Samoa 75.39
11. Japan 74.70
12. Fiji 74.57
13. Tonga 74.12
14. Italy 71.19
15. Georgia 70.76
16. USA 67.61
17. Romania 67.38
18. Canada 66.83
19. Russia 64.12
20. Uruguay 63.58
Full rankings
How the rankings work
Photo: Paul Faith/AFP/Getty Images