The idle All Whites have dropped 21 places in the latest Fifa rankings released on Thursday.
Without a fulltime coach after Ricki Herbert's departure in November, the All Whites did not play in the latest rankings period, and now find themselves at 111th between Canada and Luxembourg.
In the March rankings, New Zealand dropped just one spot - from 89th to 90th - despite a 4-2 loss to Japan in Tokyo with a youthful lineup. Since being at No 55 in the July 2013 rankings, the All Whites have more than doubled their spot, largely due to being outplayed by Mexico in their two-leg World Cup qualifying playoff.
With Neil Emblen serving as caretaker head coach, New Zealand will face South Africa, who dropped two spots to 66th, on May 30 at North Harbour Stadium in the team's only confirmed fixture in 2014.
Meanwhile, Portugal rises to No 3 in the latest FIFA rankings and fourth-ranked Colombia now leads the South American nations.
World and European champion Spain remains top, ahead of Germany. Uruguay rises one place to No 5.
World Cup host Brazil is tied for No 6 with traditional rival Argentina, which drops three places.
Though no top team played last month, the rankings movement is caused by earlier results in a four-year cycle of matches having less value.
Switzerland, Italy and Greece, rising three places, complete the top 10.
United States rises to No 13 after drawing 2-2 with No 19 Mexico.
Ivory Coast, at No 21, leads the African nations. Iran is the highest-ranked Asian confederation team at No 37.
Australia at No 59 is the lowest-ranked World Cup team.
FIFA rankings for April (March positions in parentheses):
1. Spain (1)
2. Germany (2)
3. Portugal (4)
4. Colombia (5)
5. Uruguay (6)
6. Argentina (3)
(tie). Brazil (9)
8. Switzerland (7)
9. Italy (8)
10. Greece (13)
11. England (12)
12. Belgium (10)
13. United States (14)
14. Chile (15)
15. Netherlands (11)
16. France (17)
17. Ukraine (18)
18. Russia (19)
19. Mexico (20)
20. Croatia (16)
111. New Zealand (90)
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