Chelsea's Salomon Kalou scored the only goal as Ivory Coast beat their Group B opponents, Nigeria.
In a match that saw two favourites to win the tournament go head-to-head, the Ivory Coast secured a valuable win after a moment of brilliance from Kalou in the 66th minute.
His 15-yard shot was enough, as Nigeria tried but failed to find an equaliser.
Newcastle United's Obafemi Martins nearly scored for Nigeria in the first half, but his shot was directly at the goalkeeper.
hat-trick
Both sides were represented by a wealth of Barclays Premier League talent. Chelsea's Didier Drogba captained the Ivory Coast, playing alongside Arsenal's Kolo Toure and Emmanuel Eboue, Abdoulaye Meite of Bolton Wanderers, Tottenham Hotspur midfielder Didier Zokora, and Kalou.
Nigeria, captained by Portsmouth's Kanu, included the talent of Chelsea's John Obi Mikel, John Utaka of Portsmouth, Everton's Joseph Jobo and Ayegbeni Yaukbu, and Martins.
Earlier, Namibia and Morocco went head to head in Group A. Morocco cruised to a 5-1 victory, largely thanks to a first half hat-trick from Soufiane Alloudi.
Monday's final match saw Mali and Benin complete Group B's opening fixtures. Former Tottenham striker Fredi Kanoute scored the only goal from the penalty spot to give Mali the win.
