Ivory Coast will be without Didier Zokora for their opener as the midfielder is suspended after picking up two yellow cards in qualification.
Zokora's absence intensifies the decision of coach Francois Zahoui as to who partners Kolo Toure in defence.
Zokora filled in impressively during the 2010 World Cup, while Sol Bamba was exposed at that year's Nations Cup.
Sudan are the second-weakest side at the finals according to Fifa and have a full squad to choose from in Malabo.
Ivory Coast kick off their Group B campaign as the Nations Cup's firm favourites, even though they have failed to live up to the tag in recent years.
Zokora may have inadvertently increased the pressure by suggesting that this may be the last Nations for Didier Drogba, Kolo Toure and himself.
Nonetheless, defender Emmanuel Eboue says his team can win their first Nations Cup title since triumphing in Senegal twenty years ago.
"We have been favourites before and now we need to win it - we have a great team spirit," he told BBC Sport.
Meanwhile, Sudan are looking to win a Nations Cup match outside of their homeland for the first time since 1963.
Their last victory came when winning the final itself in 1970 but they have only contested one Nations Cup in the last three decades, with their 2008 campaign proving disastrous.
Failing to score while losing 3-0 on every occasion, the objective for coach Mohamed 'Mazda' Abdallah is clear.
Haitham Mustafa will captain the side while fellow 2008 stalwart El Moez Mahjoub will try to keep his first clean sheet in the competition.