Three-time African champions, Super Eagles, have moved two places up to 43rd spot on the World football governing body, FIFA, monthly ranking.
The Nigerian side polled 681 points in the ranking posted on FIFA website on Thursday.
The AFCON 2013 winners are now seventh on the continent behind Algeria, Cote d’ Ivoire, Tunisia, Ghana, Senegal and Cape Verde Islands.
Meanwhile, the current edition of the World Ranking reveals two changes in the top 10, with Belgium overtaking Argentina to move into second place, their highest-ever position since the launch of the world ranking.
The other change sees France return to the top 10 in ninth place at the expense of Switzerland (11th, down 2).
As none of the teams in the top 20 played a match last month, all movements in terms of points and positions are down to a devaluation of past results.
This month, the biggest movers are to be found in the bottom half of the table, with Madagascar (113th, up 37) in particular benefiting from having recently played six matches and winning four to make the biggest gain of all 209 teams in the ranking.
In addition to Belgium, three other teams – Congo (47th, up 2), Timor-Leste (146th, up 5) and Bhutan (159th, up 4) – are also in their highest-ever position in the ranking.
A total of 44 matches were played in May, bringing the number of international “A” matches played so far in 2015 to 264.
More than half of the matches (26) played in May took place in Africa.