Egypt's Zamalek are aware any further slip-ups could cost them a place in the African Confederation Cup knockout stage as they host Angola's Petro Atletico in a crucial clash on Sunday.

For all their dominance in the domestic league, Zamalek flattered to deceive in Africa's secondary club competition.

They were outclassed in a 4-2 opening group-stage loss at Kenya's Gor Mahia before conceding a last-gasp equaliser in a 1-1 draw at home to Algeria's NA Hussein Dey.

The slump against NA Hussein Dey was bitterer after Zamalek produced a vivid attacking display, which has been a hallmark of their game under Swiss coach Christian Gross this season.

They spurned a handful of clear-cut chances and were punished at the death, leaving their hopes to finish as one of the top two teams in the group hanging by a thread.

Criticism is mounting as Zamalek also let slip a two-goal lead to draw 2-2 with Talae El-Geish in the Egyptian Premier League last week, having also been profligate.

Converting the numerous chances they usually create would be key to their chances against Petro Atletico, who have three points from two games to Zamalek's one.

NA Hussein Dey top the group with four points, one ahead Gor Mahia and Atletico.

"We are standing by Gross … we won't make any changes to the technical staff halfway through the season," Zamalek's hot-headed chairman Mortada Mansour said.

"We are still on top of the league and we can qualify in the Confederation Cup."

Zamalek welcome back key defender Mahmoud Alaa, who missed the previous two Egyptian league matches due to injury.

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