Portuguese Bernardo Dias scored as Petro Luanda of Angola edged Simba of Tanzania 1-0 on Sunday to pull off the only away matchday one victory in the CAF Champions League.
There were six home wins and a surprise draw for Stade Malien of Mali at four-time former champions Esperance of Tunisia before Dias struck on 78 minutes.
Petro, twice semifinalists in the premier African club competition, maintained a 100 per cent record this season having won four qualifiers ahead of the group stage.
Simba have struggled at the national stadium in Dar es Salaam, drawing both qualifiers there, and the Group D loss is an early setback.
Petro top the table with three points, followed by Esperance and Malien with one each after they drew 0-0 in Rades on the outskirts of Tunis on Saturday.
Having won four qualifiers and scored 11 goals, Esperance were favoured to make a winning start against Malien, appearing in the mini-league phase for the first time after 19 failed attempts.
Esperance, who last won the competition in 2019, dominated possession and created 24 goal attempts, but only three were on target.
Record 12-time champions Al Ahly of Egypt scored twice in the closing stages to defeat JS Kabylie of Algeria 4-1 in Cairo.
Former Aston Villa striker Mahmoud 'Trezeguet' Hassan notched two for the Red Devils and Emam Ashour completed the rout on his comeback from injury.
Ahly top Group A on goal difference from Young Africans of Tanzania, who beat FAR Rabat of Morocco 1-0 in Zanzibar City.
Zimbabwean Prince Dube was the 58th-minute match-winner for Yanga, while former champions FAR were furious after a goal was ruled offside.
The other Egyptian challengers, defending champions Pyramids, were equally convincing winners, beating Rivers United of Nigeria 3-0 at another Cairo venue.
Ahmed Atef, who managed just one goal in 16 Champions League matches last season, claimed a hat-trick. Mahmoud Mayele, whose nine goals were crucial in the last campaign, was substituted in the second half.
Pyramids share first place in Group A with Renaissance Berkane of Morocco, who were also 3-0 winners, against Power Dynamos of Zambia.
Senegalese Paul Bassene completed the scoring with his third of the African season for Berkane, whose star striker Oussama Lamlioui was unavailable.
Portuguese Nuno Santos scored twice and created the other goal as Mamelodi Sundowns of South Africa triumphed 3-1 in Pretoria against Saint-Eloi Lupopo from the Democratic Republic of Congo.
Sundowns, runners-up last season, scored twice in the second half to collect maximum Group C points with Chilean Marcelo Allende the other scorer.
Al Hilal of Sudan pipped Mouloudia Alger of Algeria 2-1 in the same section with veteran striker Mohamed Abdelrahman scoring the 75th-minute match winner.