The Pirates placed catcher Russell Martin (left hamstring) and right-hander Jason Grilli (left oblique) on the 15-day disabled list on Saturday.
Right-hander Jared Hughes and catcher Tony Sanchez were recalled from Triple-A Indianapolis to replace them.
Martin missed two games before playing Friday, only to leave after 5 1/2 innings with pain in the hip area.
Grilli was originally placed on the DL on Friday with a left oblique strain, but the move was rescinded because of a procedural error.
This is the second time Sanchez and Hughes have been with the Pirates this season. Sanchez made the Opening Day roster, while Hughes was with the Bucs earlier this week.
Tom Singer is a reporter for MLB.com and writes an MLBlog Change for a Nickel. He can also be found on Twitter @Tom_Singer. Cash Kruth is a reporter for MLB.com. Follow him on Twitter at @cashkruth. This story was not subject to the approval of Major League Baseball or its clubs.