PHOENIX -- Left-hander Wandy Rodriguez has been classified by the Pirates' medical staff as "not likely" to be able to start against the Reds this weekend.
Rodriguez departed with left hamstring tightness in the third inning of his Monday start, and on Tuesday, he underwent an MRI which showed a strain of the hamstring.
The lefty had been tentatively considered to start the Sunday finale against Cincinnati at PNC Park.
Manager Clint Hurdle was not yet prepared to name a replacement starter for Rodriguez -- or to definitely rule him out.
"We're gonna give Wandy another rehab work day," Hurdle said after Wednesday's game. "We'll get him out to the park Friday, and should have a decision sometimes that afternoon or evening."
If he can't go, candidates for that spot start include pitchers on the current staff -- Jeanmar Gomez, Chris Leroux or Justin Wilson -- or someone being recalled from Triple-A Indianapolis.
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.