Kasaya is ruled out of the all important clash for the 'Slum Boys', set to be staged at Ruaraka Grounds due to meniscus tear on his left knee.
Levis Opiyo is expected to start in the goal with Mark Kioko, who is making a return to the squad providing the cover.
Francis Kimanzi has however, been boosted by the return of Martin Ongori, who has shaken off a knock on his ankle and Tyson Otieno, back after an extended time out.
Kasaya joins Alphonce Ndonye (ankle), Samuel Olwande (knee), Ahmed Ahmad (knee), Daniel Mwaura (ankle) and Brian Nyakan (heel) on the growing injury list at Mathare United.
Mathare United are currently a place above bottom with 17 points after 19 games.
Full Squad: Goalkeepers: Levis Opiyo, Mark Kioko; Defenders: George Owino (C), Derrick Nzosi, Andrew Juma, Lennox Ogutu, Martin Ongori; Midfielders: Edward Seda, Tyson Otieno, Roy Okal, Victor Ashinga, Chrispin Oduor, Ronald Reagan, David Owino; Forwards John Mwangi, Chris Ochieng, Derrick Onyango, Elijah Mwanzia: