(AP Photo/Matt Slocum)

Jordan Zimmermann underwent an MRI exam Saturday at 11 a.m., but the Nationals were still waiting for doctors to evaluate the results as the start of their game against the Phillies neared. The Nationals hope to have word following the game, after team physician Dr. Wiemi Douoguih and the radiologist who administered the test examine the MRI.

Zimmermann left the Nationals’ 6-2 loss Friday night in the fourth inning with a right biceps cramp. Sometimes a serious elbow injury manifests as a cramp in a nearby muscle. Fluid rushes to the elbow in order to protect it, and when fluid leaves a muscle it becomes susceptible to a cramp. But sometimes muscle simply cramp. The Nationals are optimistic Zimmermann simply suffered a cramp, but the MRI will let them know.

Zimmermann did not play catch, but he participated with Nationals pitchers shagging batting practice in the outfield. When he arrived at Citizens Bank Park, he told Manager Matt Williams he felt okay.

“He was a little sore in his biceps,” Williams said. “We’re very cautious in that regard, with history, given radiating feelings of things with regard to elbows, stuff like that. We’ll see what the results are.”

Zimmermann received a normal MRI, not an arthrogram, which involves shooting dye into the area in question. When a pitcher undergoes and arthrogram, it necessitates a stay on the disabled list because of the injection. If Zimmermann’s test results do not lead to concerns about his elbow or shoulder, Zimmermann could still return to the Nationals’ rotation after the all-star break.

“It depends on what it is,” Williams said. “When I went out there last night, he said, ‘My biceps is cramping for some reason.’ If it was a biceps cramp, there’s potential. If it was something more serious than that, then probably not. As soon as we have these results, we’ll no more, and we’ll know what the protocol would be to get him back for his next start, whenever that would be.”

As of Saturday evening, the Nationals had not summoned any reinforcements from Class AAA Syracuse to Philadelphia.