Tunisian giants Esperance and Moroccan heavyweights Wydad Casablanca have conceded shock defeats on Saturday against Teungueth of Senegal and Kaizer Chiefs of South Africa to risk losing the top spots of their respective groups.
Already-eliminated Teungueth have claimed their first win of the group stage against the Tunisian champions who are leading Group D with 10 points.
The Senegalese came back from a Mohamed Ben Romdhane 28th minute-goal to a hard fought 2-1 win courtesy to goals from Serigne Niang and Baye Diop on minutes 36 and 72 respectively.
Esperance are still leading the group but Mouloudia of Algiers, who have eight points, will host Zamalek later tonight in a crucial game.
In Group C, 9-man Kaizer Chiefs defeated Wydad Casablanca to revive their hopes of reaching the quarter finals.
Bernard Parker scored the only goal of the game in the 48th minute to fire the South African to the second spot with eight points, just like Horoya of Guinea who beat Petro Atletico 1-0.
Daniel Akpeyi received a direct red card in the 41st minute while Samir Nurkovic got his marching orders in the 89th minute on a second bookable offence.
Wydad Casablanca are on top of this group with 10 points and will host Petro Atletico, who have just 1 point after five games, next Saturday in the final game of the group stage.
While Horoya will host Kaizer Chiefs in a decider that will seal the second qualifying ticket for the knockout stage.