The Teranga Lions will face Sudan on 12 and 16 November in Matchdays Three and Four of the qualifying campaign, but head coach Patrick Vieira has been forced to make changes to his squad following the withdrawals.
Watford winger Diatta sustained an injury during his club's Championship encounter against Middlesbrough on Saturday, 7 November. The 27-year-old was involved in a collision while attempting to defend an opposition attack and was subsequently substituted.
Senegal have called up Sevilla defender Arouna Sangante to replace him.
Mamadou Sarr also ruled out
Diatta is not the only player unavailable for the double-header, as Mamadou Sarr has also withdrawn after suffering a left calf injury.
The Chelsea-owned defender, currently on loan at Real Sociedad, picked up the injury during his club's 1-1 Europa League draw against Lyon.
Massiré Sylla has been called up to replace Sarr, with the midfielder receiving an opportunity to make his debut for the senior national team.
The two replacements will give Vieira additional options as Senegal prepare for their important fixtures against Sudan.
Senegal seek stronger qualifying position
Senegal began their 2027 AFCON qualifying campaign with a 1-1 draw against Madagascar before recording a 1-0 victory over Ethiopia.
The upcoming double-header presents an opportunity for the former African champions to strengthen their position in the qualification race and build momentum under Vieira.
The two matches are scheduled for 12 and 16 November, with Senegal hoping their squad changes will not disrupt preparations for the encounters.