Glasnow has been scratched from his scheduled start Sunday against the Tigers due to back spasms, Marc Topkin of the Tampa Bay Times reports.
Right-hander Erasmo Ramirez will pick up a spot start in place of Glasnow, who reportedly experienced the back issue late Saturday. The Rays are likely still gaining information on the extent of Glasnow's injury, so at this stage, the team is hoping that he'll miss only one turn through the rotation and won't require a trip to the injured list.