Elgar Watts and Boom Prinsloo have failed to recover from their injuries and will miss the Free State Cheetahs' match against the Sharks at Kings Park on Saturday.
The pair's absence will come as a blow to Cheetahs coach Rory Duncan, whose side showed much improvement against Griquas last time out.
With Watts failing to make the trip, Willie du Plessis has been restored to flyhalf, while in the only other change to the backline, Clayton Blommetjies replaces AJ Coertzen at fullback.
Up front, Prinsloo's absence has necessitated a reshuffle in the loose trio, with Jean Cook moving to the back of the scrum and Neil Claassen returning to the starting XV.
The only other change comes in the front row, where Luan de Bruin has failed to recover from his concussion. His place will be taken by Dolph Botha, while George Marich has been promoted to the bench.
Free State Cheetahs – 15 Clayton Blommetjies, 14 Rayno Benjamin, 13 Francois Venter, 12 Joubert Engelbrecht, 11 Raymond Rhule, 10 Willie du Plessis, 9 Sarel Pretorius, 8 Jean Cook, 7 Neil Claassen, 6 Tienie Burger, 5 Francois Uys, 4 Carl Wegner, 3 Dolph Botha, 2 Torsten van Jaarsveld (c), 1 Kevin Stevens.
Subs: 16 AJ le Roux, 17 George Marich, 18 Heno Venter, 19 Vincent Jobo, 20 Shaun Venter, 21 Pieter-Steyn de Wet, 22 JP du Plessis.
Photo: Charle Lombard/Gallo Images