Nigerian striker Endurance Idahor scored the winner ten minutes after the restart.

A draw at home in the round of 16 second leg will be enough for Merreikh to book a historic place in the group stage.

Merreikh's arch-rivals Hilal will be also looking to get beyond the knockout phase.

The 2007 semi-finalists face Angolan side Primeiro de Agosto away from home on Saturday.