Youngster Hossam Ashraf came off the bench to score the winner in stoppage time as Zamalek secured a hard-fought 1-0 victory over a resilient Maqassa side to make up for their previous draw in the Egyptian Premier League on Saturday.
The 19-year-old forward netted four minutes into the additional time after a goal-mouth scramble as Zamalek made their late dominance count to break the resistance of Maqassa.
Maqassa were more than a match for their illustrious opponents, moving the ball around smoothly and keeping at bay Zamalek's sources of danger, including Moroccan winger Achraf Bencharki.
But late in the game, Zamalek relied on Bencharki's compatriot Mohamed Ounajem to carve out openings as he tormented Maqassa's backline down the right flank.
The winger started on the bench but was introduced in the first half after defensive midfielder Mohamed Hassan was injured.
Zamalek have 38 points from 19 games, 15 behind runaway leaders Ahly. They are also three points ahead of third-placed Pyramids in what could be a tight race for second place, which earns qualification for the African Champions League.
Unlike their previous 1-1 draw with Ittihad, when Zamalek squandered a plethora of goal-scoring chances, they struggled for clear-cut opportunities against a well-drilled Maqassa side.
However, the first 10 minutes were exciting, with Maqassa given a penalty that was reversed after a VAR review. The technology had two more crucial contributions, with the referee chalking off two goals for Zamalek due to clear offside.
Maqassa could have snatched the lead on 35 minutes after a well-worked move, only for keeper Mohamed Abou-Gabal to block a close-range effort from Abdallah Magdi.
A dour second half came to life in the dying minutes, especially following the introduction of Zamalek's Congolese forward Kabongo Kasongo as well as youngsters Ashraf and Osama Faisal.
Maqassa's keeper made a double save from Asrhaf and Kasongo but was powerless to prevent Zamalek from netting a decisive winner just before the end.
Ounajem muscled his way down the right and crossed low for Faisal, who dragged the ball as he attempted to shoot goalwards amid a crowd of defenders. The ball then fell kindly for Ashraf to drill a low shot home and spark wild celebrations on the Zamalek bench.
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