The teams will clash once again on September 17 to determine who progresses to the second preliminary round
Uganda's Caf Champions League ambassadors Express FC took a 2-1 first-leg victory against Al Merreikh of Sudan in a match played at St Mary's Stadium on Saturday.
Erick Kambale and Martin Kizza scored for the Ugandan Premier League winners, while Bakri Elgadir found the back of the net in favour of the visitors.
Although the Red Eagles started the game slowly, they registered an opener in the sixth minute when Kambale - with an assist from Kizza - managed to beat Al Merreikh's goalkeeper, Monged Abuzaid, at close range.