His rehab was delayed one day because of wet grounds at Principal Park. Castillo was in Thursday's lineup but rain delayed the start of the game for more than one hour. Iowa manager Marty Pevey said he scratched Castillo as a precaution because he didn't want to risk having the catcher slip on the wet area behind home plate.
Castillo has been on the disabled list since June 2 with left rib cage inflammation. He did take batting practice on Thursday and caught in the bullpen prior to the game. Castillo was expected to play Saturday.
Carrie Muskat is a reporter for MLB.com. She writes a blog, Muskat Ramblings, and you can follow her on Twitter @CarrieMuskat. Joe Popely is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.