Marshall had soreness in his throwing shoulder in spring training. He remained at extended spring training before two rehab appearances in Louisville. He pitched a scoreless inning Tuesday, allowing one hit and one walk and striking out two. On Wednesday, he allowed a home run in one inning of work.
Marshall is 37-46 with a 3.77 ERA in his eight-year career.
Partch didn't allow a run in 4 1-3 innings of relief for the Reds before he was sent down Saturday. He allowed one hit and three walks.