Champions League holders, Ahly of Egypt, need a draw in their last group match to qualify for the semi-finals.
The Cairo-based side lost their last two Group B matches and will be eliminated if they lose to Asec Abidjan of Ivory Coast at home on Sunday.
Ahly have faced claims from fans of a crisis at the club despite maintaining good form in the domestic league.
Portuguese-born coach Manuel Jose denied there was anything serious to worry about.
"There is no crisis at the club, the players are tired and have been a little complacent, that is all."
Ahly are tied at the top of the Group B standings with Al Hilal of Sudan, who play at Tunisia's Esperance on Sunday at the same time as the match in Cairo.
'Unbeaten record'
Asec are two points behind and know that only a win in Cairo would allow them to progress to the semi-finals for a third successive year.
Ahly have only ever been beaten twice at home in African club competition since 1977.
Al Hilal, one of the surprise packages of this year's campaign, are already guaranteed a semi-final place but can take top spot in the group if they win in Tunis.
That would avoid a semi-final pairing against Group A winners Etoile du Sahel, who are the form side of the competition, having yet to concede a goal in five group games.
The Tunisians settled their semi-final spot after just four matches, the runner-up spot in their group has yet to be determined.
'Weakened Side'
They have a one-point advantage over third-placed JS Kabylie of Algeria and are at home on Saturday to Etoile, who are likely to field a weakened side to rest key players ahead of the semi-final.
JS Kabylie need an away win over Morocco's FAR Rabat when they meet in Rabat on Saturday.
FAR Rabat have already been eliminated from the running.
The top two sides in each group advance to the semi-finals.
The first legs of those will be played on 21-23 September and the return legs on 5-7 October.