كتب : Hatem Maher
The Bulldozer was stretchered off the field in the second half after colliding with an opponent.
"It was very painful. My knee hurt me after I fell to the ground following the collision," Zaki told FilGoal.com.
"I hope that it will not turn out to be a serious injury. I don't want to be sidelined for a long time."
Zamalek coach Hossam Hassan will be keeping his fingers crossed that Zaki recovers from the injury in time to feature in the tough Egyptian Premier League clash against leaders and surprise package Police Union on October 26.
The combative striker has produced some fine displays so far this season after returning to Zamalek in the summer following the end of his disappointing spell at English side Hull City.
The 27-year-old, who sometimes played as a lone frontman, scored three goals in the Cairo side's first seven league games.
"We can't determine the extent of Zaki's injury now. He will undergo scans shortly," Zamalek doctor Mostafa Al-Monayeri said.
Ivorian striker Abou Kone is nursing an elbow injury while Iraqi Emad Mohamed went AWOL amid reports linking him with a move to Iranian club Esteghlal.
If Zaki misses the Police game, Hassan will be left with one recognized striker at his disposal in Ahmed Gaafar.
Zamalek lie second in the 16-team league table with 14 points, one behind Police.