The Riders will not face star QB Bo Levi Mitchell on Saturday. The Stampeders placed Mitchell on the 6-game injured list Friday.
Mitchell injured the pectoral muscle on his throwing side in Week 3. He will be replaced in the starting lineup by Nick Arbuckle.
The Stamps will also be without starting running back Don Jackson. He has also been placed on the 6-game injured list with a concussion. And starting National receiver Juwan Brescacin is out for Saturday (concussion). He is on the 1-game injured list.
The Stampeders website lists 11 players on the 6-game injured list. Six of them were expected to be starters this season.