The Cardinals placed Kwang Hyun Kim on the injured list before Saturday's doubleheader, and a reason for the move was not immediately advertised.
The team has planned a public update.
Kim was scheduled to start Sunday's night game at Wrigley Field, and that was going to allow the Cardinals to stack starters Adam Wainwright and Dakota Hudson for Saturday's doubleheader. Kim's absence will force a rewrite of the rotation.
The Cardinals also activated Andrew Miller from the injured list, and he will be available for Game 1 of the doubleheader. Rookie reliever Nabil Crismatt was added to the roster for both games of the doubleheader as the Cardinals' 29th man.