Ahly needed a stoppage-time header from veteran striker Emad Meteb to edge out an unyielding Petrojet side 1-0 away from home in the Egyptian league on Saturday.
After struggling throughout regular time to find the back of Petrojet's net, substitute Meteb headed the winner in the first minute of injury time to give Ahly all three points.
Ex-Ahly midfielder Ahmed Hassan was en route to frustrating his former side as Petrojet manager in his second game against the Cairo giants, but again failed as his team were defeated.
The Reds, who finished runners-up to champions Zamalek last season, have made it three wins out of three games to top the league table.
On the other hand, Petrojet are now 10th in the league table with a single win that came at the expense of Smouha last week.
Dreary affair, Meteb heads in late
In a largely insipid first half, where the ball was mainly confined to the midfield, the first real chance came after 32 minutes when Saleh Gomaa struck from outside the box, but keeper Mohamed El-Shennawi was there to block his effort.
Petrojet's Karim Tarek then replied with another shot after evading center-back Mohamed Naguib just three minutes later, but his effort hit the side netting.
At the stroke of half time, right-back Ahmed Fathi was unlucky to see a strike from outside the area narrowly go wide of the post as both sides went into the dressing rooms with the score line nil-nil.
Things did not change much after the break, with both sides unable to pose a genuine threat on goal, but this time it was the hosts who tested the opposition keeper first.
With the goals clear, Mohamed Ragab latched onto a long through ball to hold in-form center-back Ahmed Hegazi behind his back, before seeing his eventual shot being parried by keeper Sherif Ekrami on 58 minutes.
Ahly's first chance after the break arrived in the 70th minute when an Abdallah El-Saied shot missed the target, before Moemen Zakareya had another one saved by the keeper.
But just as the game seemed heading towards a goalless draw, 32-year-old Meteb gave Ahly all three points when he headed in a pin-point cross from left-back Sabri Rahil following a superb pass by skipper Hossam Ghaly.
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