The Flamingos thrashed their hosts 6-1 to put themselves in a very good position to qualify for the second round.
Yemisi Samuel had a hat-trick after scoring in the 11th, 85th and 91st minutes.
Rofiat Imuran bagged a brace on 38 and 65 minutes while Chinyere Kalu scored in the third minute.
Reacting to the win, the Sports Minister wrote on his Twitter handle: “Congratulations! Guinea 1-6 Nigeria: Flamingos record a big away win at September 28 Stadium. The return leg with the Guineans will be on March 14 in Lagos.”
