Egypt's Ismaily needed two late goals to break down a resilient Terrible CO side, beating the Madagascar club 2-0 in Alexandria in the first leg of the African Confederation Cup round of 32.
The Dervishes scored in a three-minute second-half spell to ensure they would head into the second leg in a fortnight as favourites to reach the last 16 of Africa's secondary club competition.
Midfielder Ahmed Khairy broke the deadlock in the 77th
minute with a precise shot from inside the area.
Ghanaian forward John Antwi, 20, doubled the lead with 10 minutes remaining when he skillfully skipped past a challenger, burst into the area and fired home from a tight angle.
The Confederation Cup has eluded Egyptian clubs since it was introduced in 2004 by merging the African Cup Winners' Cup and the CAF Cup in a single competition.
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