Misfiring Zambia begin the defence of the African Nations Cup title against Ethiopia and a new-look Nigeria face Burkino Faso in Group C in Nelspruit's Mbombela Stadium on Monday.
Nigeria, Africa's most populous country embarrassingly missed out on the last edition of the Nations Cup and have undergone a controversial overhaul under new coach Stephen Keshi, reports Reuters.
He has left out the likes of Peter Odemwingie and Obafemi Martins and put faith in a mix of young players from the Nigerian premier league and clubs in Europe, topped by the expertise of Chelsea pair John Obi Mikel and Victor Moses.
They are up against a Burkina Faso side that have become consistent performers but are still not regarded among the tournament heavyweights.
Although Zambia have sought to replicate the preparations that preceded their win in last year's Nations Cup finals by staying in the same hotel in Johannesburg, using the same training facilities and playing some of the same pre-tournament opponents, they have run into a crisis of confidence after failing to score in their last four warm-up games.
Monday's matches follow a 1-0 victory for Mali over Niger in Group B on Sunday and a 2-2 draw between two former champions - Ghana and the Democratic Republic of Congo.