Ireland have dropped two places in the latest Fifa world rankings despite their recent win over 14th-ranked Switzerland.
Both the USA and Poland have leapfrogged Martin O’Neill’s team - now ranked 31st.
Northern Ireland’s draw with Wales and their recent win over Slovenia brings them up to their highest ever ranking - 26th place.
Argentina moved top as South America dominated the monthly rankings on Thursday with five teams, half of the continent's total, in the top 10.
Argentina’s World Cup qualifying wins away at Chile and home to Bolivia dislodged Belgium, who had been leading for the previous five months but dropped into second.
Despite the defeat, Chile climbed to third, an all-time high, with Colombia one place behind them in fourth, Brazil seventh and Uruguay ninth.
The rankings did not make such happy reading for Asia, who had only two teams in the top 50, Iran in 42nd and regional champions Australia in 50th.
Algeria were African’s highest-placed team in 33rd, one ahead of Ivory Coast, while 16th-ranked Mexico led the way for CONCACAF.
Three-times continental champions Nigeria dropped to 67th after failing to qualify for next year’s African Nations Cup.
Rankings: (previous month in brackets) 1. Argentina (2) 2. Belgium (1) 3. Chile (5) 4. Colombia (8) 5. Germany (4) 6. Spain (3) 7. Brazil (6) 8. Portugal (7) 9. Uruguay (11) 10. England (9).