Mountcastle (foot) is slated to have an MRI on Sunday, Andy Kostka of TheBaltimoreBanner.com reports.
Mountcastle exited Saturday's 6-2 win over San Francisco after stumbling and diving as he approached second base on a double. He was immediately replaced by a pinch runner and exited the field with a trainer. Clarity about Mountcastle's injury and a timeline for his return to action could come once the results of his imaging are in.