Marmoush (C) celebrates Egypt s winner against Libya (Photo: Ahram)
The Stuttgart on-loan winger let fly from the edge of the area with a delightful curler four minutes into the second half to settle a tight contest and give Egypt a precious victory in their quest to reach the final two-legged playoff for a place in next year's Qatar finals.
He was a surprise inclusion in Egypt's starting line-up, with new coach Carlos Queiroz making the bold choice after the 22-year-old produced a string of fine displays lately. He was named the Bundesliga's best young player for September earlier in the day.
Marmoush, who came through the youth ranks of Egypt's Wadi Degla, produced a lively performance to wreak havoc down the left flank, stealing the limelight from Liverpool star Mohamed Salah, who was well shackled on the right.
Egypt labored for much of the game but did enough to bag all three points and overtake Libya on top of the group. The Pharaohs have seven points from three matches, one ahead of Libya and four clear of Angola. Gabon lie at the bottom with a solitary point.
The seven-time African champions meet Libya in Benghazi in another crucial clash on Monday.
Wolfsburg-bound Marmoush, who played four matches for Egypt's U23 side but had not made any appearances with the senior team, played alongside veteran playmaker Abdallah El-Said and Salah to support lone striker Mostafa Mohamed.
But despite dominating proceedings, Egypt seemed to lack harmony in the final third as Libya's well-drilled backline restricted them to a couple of chances in the first half.
Egypt's first chance fell to El-Said after 16 minutes when the Pyramids FC schemer robbed a Libya full-back, jinked into the area and cut inside but his shot was deflected by a sliding tackle from Sanad Al Warfali.
Two minutes later, Mohamed just failed to get on the end of a diagonal Salah cross at the far post with the goal gaping.
Libya could have scored against the run of play four minutes before the break though.
A rare foray forward saw Muaid Ellafi whip in a cross from the left that eluded Egypt's left-back Ahmed Fatouh and fell to striker Mohamed Zaabia, whose angled low shot struck the outstretched leg of keeper Mohamed El-Shennawi and came back off the post.
Marmoush settled Egypt's nerves in the 49th minute when he gathered the ball on the edge of the area, twisted past a challenger and fired an unstoppable right-foot shot into the roof of the net.
Libya made a raft of substitutions to beef up their attack, which included the introduction of Esperance's in-form winger Hamdou Elhouni, but they hardly threatened El-Shennawi.
It was Egypt who could have doubled their advantage but Mostafa sent a free header straight into keeper Mohamed Nashnush's hands. The hosts were comfortable in the latter stages to protect their lead and give Queiroz a valuable win in his first competitive match in charge.
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