Veteran forward Mputu is recovering from malaria while Malango is injured.
Mputu featured in last weekend’s league match against Saint Eloi Lupopo, which Mazembe lost 1-0.
“This Tuesday, the team will have two training sessions before the next day's trip. Sessions which, hopefully, will have Ben Malango participating as he is recovering from injury as well as Tresor Mputu who has been getting treatment for malaria since Monday,” said the club on their website.
The Congolese giants were initially scheduled to leave for Dar es Salaam on Tuesday, but will travel on Wednesday instead.
They face Simba, who are unbeaten at home having defeated Al Ahly and AS Vita in this season’s continental competition.
At the Benjamin Mkapa National Stadium, Simba will provide a stern test for Mazembe, who are seeking a sixth Champions League crown.