The White Knights slumped to their first loss in the Arab Cup after a 1-0 defeat to Saudi side Al-Shabab on Monday.

Argentinian forward Ever Banega scored the winner, converting a controversial penalty one minute before halftime.

The referee awarded the penalty to the Saudi side after a VAR check, as the ball touched the hand of defender Mohamed Abdel-Ghani inside the area.

"We produced a balanced performance during the first half," Osorio told the post-match news conference.

"But the referee awarded a false penalty for the Saudi side. "

"Our performance improved in the second half, but we failed to score. We deserved to score at least one goal given our performance during the game, especially in the second half," he added.

The Cairo giants have filed a complaint against Abdel-Wahed Herweda who officiated the game.

The loss reduced Zamalek's hopes of reaching the next round, as they now need to beat Cristiano Ronaldo's Al-Nassr on Thursday in the final matchday of the Group stage.

Zamalek are second in the Group with three points, one point behind leaders Al-Shabab.

Meanwhile, Al-Nassr sit in third place with one point, but they are set to face minnows Monastir, who lies at the bottom of the Group, later on, Monday.

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