Egypt will host Mauritania on Friday at Cairo International Stadium before travelling to Nouakchott for the return leg on 15 October.
The EFA said that Zamalek's midfielder Nabil Emad sustained a hamstring strain, which ruled him out of the first leg.
However, the medical staff are trying to help him get fit for the return leg.
Saber, 23, has received his first senior national team call-up.
He was a key player for Egypt’s U23 team under coach Rogério Micale and showcased impressive performances during the Paris Olympics.
The Pharaohs now lead their group with six points from two wins against Cape Verde and Botswana.
(For more sports news and updates, follow Ahram Online Sports on Twitter at @AO_Sports and on Facebook at AhramOnlineSports.)
Short link: