Egyptian giants Ahly said on Saturday they would file a complaint with the Confederation of African Football (CAF) against what they described as costly refereeing errors in the Champions League.

The Red Devils were enraged following their 1-0 loss at Tunisia's Etoile Sahel in their opening group-stage game of the African Champions League on Friday, saying they were the victims of a glaring refereeing mistake.

They played with ten men for most of the game after central defender Ayman Ashraf received his marching orders on 13 minutes for a last-man foul on an Etoile forward, although television replays suggested that the straight red card was harsh.

When Ashraf committed the foul, the Etoile man was not in a certain-goal position as he anticipated a long ball.

With one man down, Ahly, who are eyeing their first Champions League title since winning the last of their record eight crowns in 2013, failed to mount any threatsas a second-half goal from Yassine Chikhaoui gave Etoile an opening win.

"Ahly's board of directors decided to file an urgent complaint to CAF over the refereeing injustice that the first team has been subjected to in the Champions League in recent years, especially what happened against Etoile Sahel," the club said in a statement on their official website.

"The Botswanian referee committed many mistakes … that directly affected the outcome of the game.

"Chairman Mahmoud El-Khatib instructed the concerned departments of the club to prepare all the documents that show the clear and unacceptable refereeing errors in the last game."

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