Egypt's Ahly were hoping their recent African Super Cup triumph would put them on the right track following a poor run but they were hardly convincing in a stunning 1-0 defeat at Tanzania's Young Africans in the first leg of the Champions League round of 32.
Nadir Haroub scored the winner with eight minutes remaining to give the unfancied hosts a valuable win as they seek to cause a huge upset and eliminate the eight-time Champions League winners.
The second leg will be played next Sunday at the Arab Contractors Stadium in Cairo.
Ahly were buoyed by their recent 3-2 victory over Tunisia's Sfaxien in the Super Cup but they were largely toothless against Young Africans.
They started with two strikers in Mohamed Nagy 'Gedo' and the in-form Amr Gamal while Burkinabe attacking midfielder Moussa Yedan made his first start after joining in January.
Gedo and Gamal were lively upfront but they could not make their efforts count. Gamal appealed for penalty when he was tripped by Young Africans keeper following a one-on-one towards the end but the referee waved play on.
The match was briefly halted in the second half after the home fans hurled bottles onto the pitch.
Haroub put Young Africans ahead on 82 minutes when he headed home a cross. Ahly piled on pressure in the latter stages in a bid to equalize but the Tanzanian outfit held firm to spring a surprise.
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