CAF Champions League title-holders Al Ahly dropped points for the second successive weekend when held 0-0 at home by Chabab Belouizdad of Algeria on Friday.
After an away draw against Young Africans in Tanzania six days ago, the record 11-time African champions were expected to collect maximum points from the Group D match in Alexandria.
But a defiant Belouizdad defence, backed by former Algeria goalkeeper Rais M'Bolhi, contained an Ahly attack including Mahmoud Kahraba, Hussein el Shahat and South African Percy Tau.
The result was a major boost for Belouizdad, who conceded an added-time goal to lose away to Medeama of Ghana last weekend.
Medeama could not achieve back-to-back home victories, however, as they surrendered the lead in a 1-1 draw against Young Africans in Kumasi.
Jonathan Sowah, recalled after being ruled out of the Belouizdad match by suspension, converted a 27th-minute penalty for group debutants Medeama.
It was his third goal of the African campaign, and Ivorian Pacome Zouzoua also scored for a third time in the Champions League this season by equalising nine minutes later.
Ahly have five points, Medeama and Belouizdad four each and Young Africans two at the halfway stage of the mini-league. Group winners and runners-up qualify for the quarter-finals.
On a night when three matches produced only three goals, the best came from Cameroonian Jacques Mbe, which gave Etoile Sahel of Tunisia a 1-0 win over Al Hilal of Sudan in Rades near Tunis.
With just two minutes of regular time remaining, Mbe unleashed a thunderbolt past Ivorian goalkeeper Issa Fofana to earn Etoile their first points in Group C.
Petro Luanda of Angola, who play on Saturday, top the table with six points while Hilal, four-time champions Esperance of Tunisia and Etoile have three each.