BAMAKO (Reuters) - Two World Cup finalists - Nigeria and South Africa - will have their credentials further examined at the African Nations Cup finals on Sunday as the tournament in Mali reaches the quarter-final stage. Nigeria renew their old rivalry with Ghana at Bamako's March 26 stadium while South Africa travel to the provincial mining town of Kayes for a potentially arduous clash with the host country.

The two other quarter-finals at the Nations Cup finals will be played on Monday with defending champions Cameroon facing their predecessors Egypt at Sikasso and World Cup finalists Senegal meeting the Democratic Republic of Congo in Bamako.

Nigeria had little trouble negotiating their way through the opening round at the Nations Cup but scored just twice in their first three games in far from convincing performances.

The much-vaunted strike partnership of Arsenal's Nwankwo Kanu and Bundesliga-based Victor Aglai has been overshadowed by Ukrainian-based Julius Aghahowa, who scored the winners against both Algeria and Liberia in Group A last week.

HEAVILY FANCIED

But the Super Eagles will still be heavily fancied to beat the young Ghanaian side, who staged a miraculous recovery on Wednesday to clinch a place in the last eight.

Two goals in the last two minutes from Isaac Boakye saw Ghana overturn a one-goal deficit against Burkina Faso in Mopti and claim second place in Group B behind South Africa.

Nigeria beat Ghana 3-0 in their last meeting in July when the Super Eagles clinched their World Cup place in a one-sided match in Port Harcourt.

Coach Shaibu Amodu said he expected Sunday's match to be a much tougher encounter but he was also convinced the Nigerian side would show a marked improvement from their three previous matches at the Nations Cup finals in Mali.

Ghana have injury concerns with wide player Michael Essien, from French club Bastia, and striker Baffour Gyan doubtful for the match.

The side are also still having to deal with the fallout over the sending home of key defender Samuel Kuffour, the African Footballer of the Year candidate from Bayern Munich.

Captain Emmanuel Duah is the latest to criticise the decision by coach Fred Osam Dudou, who described Kufour as a 'disruptive influence'.

'I don't think it was right to send him home, he's a very influential player,' said Duah.

Mali play their first match of the tournament away from the 50,000-capacity March 26 stadium and its wide playing surface when they meet the South Africans at Kayes, a stadium seating 15,000 and with a narrow and bumpy pitch.

Defender Adama Coulibaly returns from suspension while South Africa are expected to start captain Shaun Bartlett, now recovered from the calf muscle injury which has restricted his Nations Cup participation to just 17 minutes.

'We have the confidence back in our side but we expect this will be no easy assignment,' said South African coach Carlos Queiroz on Saturday.

South Africa started the tournament with two goalless draws but won convincingly against Morocco on Wednesday to finish top of the group.

South Africa and Mali meet at 1600 GMT in Kayes with the Nigeria-Ghana match kicking off three hours later.