Ahly's interim coach Mohamed Youssef said that his players suffered from "altitude sickness" as they were beaten by Jimma Aba Jifar of Ethiopia 1-0 on Sunday but still managed to reach the Champions League group stage.
The Cairo giants had a 2-0 first leg advantage but looked lackluster in Addis Ababa and were under constant pressure throughout the match.
"The players were very tired due to the lack of oxygen in the air and it affected us a lot. I thank them for their effort throughout the game," Youssef said after the game.
The Ethiopian capital sits at 2.355m above sea, causing fatigue to those who are not accustomed to it.
"We should have used our first leg leverage. We could have scored five, six or seven goals and killed the tie. It is a lesson that we should learn," Youssef added.
"We had very limited options in the squad due to injuries and absences but what's important is that we reached the group stage and a new phase will start," he concluded.
The draw of the group stage will be held on Friday.
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