Brendan Rodgers' 17-game unbeaten run came to an end in a derby defeat against his former players.
The Northern Irish manager's Al Quadsiah side faced the challenge of Al-Ettifaq, featuring Moussa Dembele and Jack Hendry.
The ex-Celtic duo both found the net, contributing to a 3-2 victory.
Al Quadsiah took the lead with a goal from Julian Quinones.
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But their lead was short-lived, as Hendry equalised, and Dembele put Al-Ettifaq ahead with a header shortly after half-time.
Former Liverpool midfielder Georgionio Wijnaldum put Steven Gerrard's old side further ahead from the penalty spot.
Another Quinones goal late in the game was only consolation.
Al-Quadsiah finished the game with nine men after Mohammed Waheeb Abu Al Shamat was sent off in the first half and Gaston Alvarez joined him deep into stoppage time.
Rodgers took charge of the side in December.
His 17-game unbeaten run came to an end against their rivals in the Easter Derby.
Dembele, under Rodgers' management at Celtic, left the club after a conflict arose from a perceived breakdown in trust over a potential transfer.
Dembele took to social media following the exit, writing: "A man, without his word, is nothing. A real man keeps his word."
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