Liverpool teammates and national team captains, Salah and Keita were creative but failed to score in a Group D first round match that offered little excitement for the Cairo crowd.
Substitute Mohamed, who plays for Turkish giants Galatasaray, ended the deadlock on 87 minutes from time with a shot that Mouctar Diakhaby deflected past goalkeeper Ibrahima Kone.
New Egypt coach Ehab Gabal promised a “different playing style” after the twin disappointments of losing to Senegal both in the Cup of Nations final last February and in a World Cup play-off one month later.
But he made a forgettable debut and more will be expected of the Pharaohs when they play Ethiopia on Thursday before Salah takes a well deserved break.
In the same group, Malawi edged Ethiopia 2-1 in a clash of 2021 Cup of Nations qualifiers, with all the goals in Lilongwe coming from penalties.
Frank ‘Gabadinho’ Mhango fired spot kicks into the right corner and the middle of the net to give the Flames a two-goal half-time advantage.
But Ethiopia created a tense finish by halving the deficit midway through the second half when Abubeker Nassir converted the third penalty of the match.
Egypt are favoured to win the group as they chase a record-extending eighth title, with Guinea and Malawi fighting to come second, so the stakes will be high when they meet on Thursday in Conakry.
Qatar World Cup qualifiers Ghana battled in Group E against the Central African Republic, who forced a 1-1 draw despite playing in Angola because they do not have an international-standard stadium.
After hammering Madagascar 3-0 on Wednesday, Ghana would have expected to pick up three more points at a neutral venue against rivals 27 places lower in the world rankings.
– Wild Beasts surprise Ghana –
The four-time African champions went ahead on 17 minutes when a low, swerving shot from outside the box eluded the outstretched hand of goalkeeper Alladoum Kolimba.
But a scarcity of possession did not prevent the Wild Beasts levelling four minutes before half-time as France fourth-tier forward Karl Namnganda burst forward and rifled the ball past Lawrence Ati-Zigi.
Namnganda scored the goal that gave the Central African Republic a stunning World Cup qualifying victory in Nigeria last year.
Despite the setback, Ghana top the section on goal difference from Angola, who conceded a soft goal but equalised soon after to force a 1-1 draw with Madagascar in Antananarivo.
A Njiva Rakotoharimalala tap-in put the Malagasys ahead under recalled French coach Nicolas Dupuis and Jacinto ‘Gelson’ Dala levelled by heading in a far-post cross.
It was a potentially vital away point for the Angolans in the probable contest for second spot behind Ghana, whose last Cup of Nations triumph came 40 years ago.
Group J pacesetters Tunisia had a similar matchday 2 experience to Ghana, drawing away to a lower ranked side after launching their campaign with a big home victory.
After thrashing Equatorial Guinea 4-0 in midweek, the Carthage Eagles twice struck the woodwork as they drew 0-0 with Botswana in Francistown.
Tunisia and Ghana now head to Tokyo for Kirin Cup semi-finals against Chile and Japan respectively on June 10 and both will play again four days later, either in the final or third place play-off.
After a busy weekend of qualifiers, there is only one fixture on Monday with Equatorial Guinea hosting Libya, who have maximum points after beating Botswana.