Al-Ahly surrendered a 29-month unbeaten record in Egypt after crashing 3-0 to Ismailia in a top-of-the-table league clash at the weekend.
The Cairo team, who finished third in the FIFA Club World Cup during December, last lost a domestic fixture in July 2004 when beaten 2-1 by Arab Contractors in the Egyptian Cup final.
Ahly went unbeaten through the last two national championship seasons and this was their first league loss since falling to bitter domestic rivals Zamalek 31 months ago.
Last year Ahly lost only three times, against Internacional of Brazil in a Club World Cup semi-final in Japan and away to CS Sfaxien of Tunisia and ASEC of Ivory Coast in the CAF Champions League.
Mohamed Fadil scored twice against his former club and Abdullah al-Sayed was also on target for Ismailia, who trail Ahly by six points with 14 rounds to go in the title race.
Champions League title holders Ahly finished with 10 players as star midfielder Mohammed Aboutraika was carried off after Portuguese coach Manuel Jose had made three substitutions.