Castillo (shoulder) will open the season on the injured list, Bobby Nightengale of The Cincinnati Enquirer reports.

EDGE Analysis

Castillo has been battling shoulder soreness this spring. Reports from last week indicated that he might have a tough time getting ready by Opening Day, and that's now been officially confirmed. He's been going through a throwing progression and is expected to return sometime in April, but he'll miss at least a turn or two in the rotation to start the year. His absence, as well as the absence of Mike Minor (shoulder), could give rookies Hunter Greene or Nick Lodolo the chance to break camp in the rotation.