Egypt's Zamalek failed to break down DR Congo giants and fellow five-time winners TP Mazembe in a goalless African Champions League draw in Cairo on Friday, although they remain in pole position to reach the knockout phase.
Already-qualified Mazembe were lucky not to concede in the first half but looked solid in the second period to keep Zamalek at bay.
The hosts were largely affected by the absence of Moroccan forward Achraf Bencharki, who was injured in the warm-up. They could not avenge a bitter 3-0 defeat by Mazembe in Lubumbashi in their opening Group A encounter.
Mazembe top the group on 11 points with one match remaining, three ahead of Zamalek. Angola's Primeiro de Agosto and Zambia's Zesco United, who meet in the other group game on Saturday, have two points apiece.
Should Primeiro de Agosto fail to beat Zesco away from home, Zamalek will secure passage to the last eight before meeting the Angolans in their final match, given their better head-to-head record over Zesco.
Zamalek completely dominated proceedings in the first half, with lone striker Mostafa Mohamed a constant threat upfront.
With Mazembe pegged back from the early stages, Zamalek could have gone ahead as early as the eighth minute when Mohamed's back-heel pass released deep-lying forward Youssef Ibrahim, whose angled shot was blocked by keeper Sylvain Gbohouo.
Gbohouo produced an even more impressive one-handed save to keep out a curling shot from Mohamed after 19 minutes for Zamalek's best chance.
Mohamed, who is known for his aerial prowess, came close again on 35 minutes when his header whizzed just wide from a right-wing cross.
For all the excitement of the first half, the second was a disappointing affair, with Zamalek's fitness flagged as Mazembe looked slightly better.
The visitors created the only meaningful chance after the break when Isaac Tshibangu bamboozled Emam and hit a shot that was saved by keeper Mohamed Abou-Gabal at his near post in the 52nd minute.
The introduction of Moroccan winger Mohamed Ounajem and Mostafa Fathi did little to spur Zamalek into action, with Mazembe holding on to ensure they would advance as the group winners.
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