Castro will not make his scheduled start against the Phillies on Wednesday, Roch Kubatko of MASN Sports reports.
Castro was set to make a spot start for the Orioles on Wednesday, but Andrew Cashner will get the nod instead following Tuesday's postponement. Castro's role going forward remains unclear with Chris Tillman (back) on the disabled list, as both Castro and David Hess are candidates to step into the starting rotation.