كتب : Ahmad Saied
Guinea were held to a 1-1 draw by minnows Namibia, who lost their opening two games to Morocco and Ghana.
"It's good to qualify for the quarter-finals, but our game was very poor today, we didn't play very well," the Celtic man admitted on BBC Sport.
"We'll have to do far better if we want to win in the quarter- finals, and we'll miss Pascal Feindouno."
Captain Feindouno misses the quarter-final clash as he serves the second of a two-game ban.
Guinea finished in second place of Group A.
Their opponent in the next round will be known later on Tuesday, when Ivory Coast play Mali and Nigeria take on Benin.