Zimbabwean playmaker Billiat, whose future at Chloorkop is in doubt as he stalls on signing a new deal in favour of an overseas move, is said to be carrying a hip injury.
Ivorian attacker Zakri is nursing a groin complaint, while utility player Mashaba faces a lengthy spell on the sidelines following surgery on a torn Achilles.
Sundowns released an injury list on their website, which reads: 'Billiat (hip flexor), Zakri (groin), Mashaba (torn Achilles), Tiyani Mabunda (groin), Keletso Makgalwa (groin), Sibusiso Kumalo (groin), Kennedy Mweene (hamstring), Siyanda Zwane (toe blisters).'
Downs will tackle Ea Lla Koto at Goble Park Stadium (18h00) looking to bounce back from a 2-1 defeat to Polokwane City, having opened their league campaign with a 2-0 win over Tshwane rivals SuperSport United.
Coach Pitso Mosimane also has an eye on Sunday's CAF Champions showdown with Morocco's Wydad Casablanca at Lucas Moripe Stadium (15h00).