Manager Joe Maddon said that Underwood, who was reassigned to minor league camp Monday, has been held back during spring training due to stiffness in his right elbow, Carrie Muskat of MLB.com reports.
It doesn't sound like too much of an issue, but throwing elbow issues are never good to hear. He could continue to be held back for a few more days to ensure proper healing, but his status should become clearer in the coming days whether he sits out or not.