Cubs C Castillo leaves with left rib contusion
Castillo was struck by a foul ball in the first inning on Friday. A trainer and manager Rick Renteria came out to check on him, but Castillo managed to finish the top of the first.
Rafael Lopez hit for Castillo in the bottom half, and then stayed in the game to catch.
The Cubs announced the injury in the fourth inning, and said Castillo is undergoing further evaluation.