Locke, diagnosed with tightness, will give way to Jay Jackson. A 26-year-old righty who has spent six years in the organizations of the Cubs and Marlins, Jackson has pitched two shutout innings in relief this spring.
Locke was sporting therapeutic bandage strips in the affected area Tuesday morning in the Pirates' McKechnie Field clubhouse.
Pirates manager Clint Hurdle could not provide an update on his pitcher's status following the Pirates' 5-2 victory over the Detroit Tigers.
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. This story was not subject to the approval of Major League Baseball or its clubs.