Nationals manager Davey Johnson said he's "probably not that confident" that Ross Detwiler (back) will be able to make his next start.
Advice: It's not clear whether a disabled list stint will be required, but it sounds like Detwiler won't be used at least one time through the rotation. The lefty underwent an MRI Thursday, though the specific results of it are not known. The Nats are expected to turn to their bullpen for a spot start, with Craig Stammen viewed as the likely favorite over Zach Duke to get the nod.
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