A shock-riddled Africa Cup of Nations in Ivory Coast has reached the round of 16 with four ties between winners of the competition highlighting a four-day schedule that kicks off on Saturday.The clashes of champions pit Nigeria against Cameroon, Egypt against Democratic Republic of Congo, title-holders Senegal against Ivory Coast and Morocco against South Africa.None of the other four matches feature a former winner, but 2015 semi-finalists Equatorial Guinea will attract attention after topping a group including more fancied Nigeria and Ivory Coast. Here, AFP Sport looks at the eight matches and predicts which countries will advance to the quarter-finals of the African football showpiece.SaturdayAngola v NamibiaThis clash of southern Africa neighbours was totally unexpected given Angola had not gone beyond the group stage since being 2010 hosts and Namibia had been winless in three earlier appearances.Angola overshadowed Algeria and Burkina Faso to top Group D with Gelson Dala scoring twice while Namibia stunned Tunisia, were crushed by South Africa, then exceeded expectations to hold Mali.Prediction: Angola to win  Nigeria v CameroonWhen it comes to finals in the Cup of Nations Cameroon have won all three against Nigeria, who got the better of the Indomitable Lions in three other meetings. A Victor Osimhen-led Nigerian attack have found goals hard to come by with just three in three matches, including a penalty and an own goal, but the Cameroon defence is far from impregnable. Prediction: NigeriaSundayEquatorial Guinea v GuineaEquatorial Guinea captain Emilio Nsue, the leading tournament scorer with five goals, told his team “not to get carried away” after topping Group A through a shock 4-0 win over Ivory Coast. Guinea are a team who regularly reach the knockout phase, then make little impact. They will hope fit-again Serhou Guirassy can recapture his Bundesliga scoring form. Prediction: Equatorial GuineaEgypt v Democratic Republic of CongoIt would have been hard to imagine before the tournament began that record seven-time champions Egypt would qualify without winning a match, but they drew all three in Group B.The absence of injured talisman Mohamed Salah is a massive blow against a workmanlike Congolese side, led by impressive centre-back Chancel Mbemba, that also progressed after three draws. Prediction: EgyptMondayCape Verde v MauritaniaThis is another tie that no neutral observer would have foreseen before Mauritania, after two unlucky losses, stunned two-time champions Algeria to finish third and squeeze through.   They need to avoid conceding free kicks in their half as Cape Verdean Bebe scored from a 40-metre set-piece against Mozambique. Holding Egypt suggests they will not be pushovers.Prediction: Cape VerdeSenegal v Ivory CoastWhile one of the favourites, Senegal have lost both previous Cup of Nations matches against Ivory Coast and must bury a jinx which has seen the last six holders fail to retain the trophy. Ivory Coast fired coach Jean-Louis Gasset after being humiliated by Equatorial Guinea and caretaker Emerse Fae knows only a drastic improvement when attacking will offer any hope.Prediction: SenegalTuesdayMali v Burkina FasoA clash of former runners-up with Malian Lassine Sinayoko and Burkinabe Bertrand Traore among eight players who have scored twice so far in the Ivory Coast.Both sides are physically powerful, with Mali exploiting that factor in a group victory over South Africa, and they have been more impressive than rivals who surprisingly fell to Angola.Prediction: MaliMorocco v South AfricaWhile Morocco will be favourites, they have won only one of five meetings with South Africa, who rank among the most unpredictable teams in this tournament. Outmuscled by Mali, they thrashed giantkillers Namibia, then fought a dour goalless draw with Tunisia. Morocco have several potential match-winners while South Africa rely on Themba Zwane. Prediction: Morocco