Last season's beaten finalist Al Ahly, the most successful team in the competition's history, took just four points from its first three Group A games.
Defeat away to Botswana side Township Rollers would have left Egyptian champion Al Ahly on the brink of an early exit, but Coulibaly came up trumps with a powerful 81st-minute winner from a corner.
Group leader ES Tunis secured qualification with a 1-0 win at Kampala City of Uganda, which had goalkeeper Charles Lukwago dismissed late in the game for bizarrely electing to roughly lift an injured player on to a stretcher.
ES Tunis hit a 41st-minute winner when Haythem Jouini got in behind and side-footed a classy finish into the top-right corner.
Wydad eased past Horoya 2-0 thanks to first-half goals from Cheick Camara and Mohamed Ounajem, moving last season's champion three points clear at the top of Group C with two games remaining.
In the sole Group B game, leader TP Mazembe dropped points for the first time in this season's competition as it was pegged back in a 1-1 draw at MC Alger, which occupies second spot.