(Toni L. Sandys/The Washington Post)

Right-hander Taylor Jordan, a member of the Nationals’ opening day rotation as a fill-in for Doug Fister, has not pitched since June 5 because of elbow soreness the Nationals are working to precisely diagnose.

Jordan recently visited team physician Dr. Wiemi Douguih for a second opinion “to see what’s going on,” General Manager Mike Rizzo said. “He had an MRI. The MRI is fine. We wanted to see, what’s the discomfort coming from?”

Jordan underwent Tommy John surgery in 2011. The Nationals are confident his current elbow problem will not lead to a second elbow ligament-replacement operation.

“We’re not too worried about that,” Rizzo said. “The doctors told me that’s not what they’re thinking about. They want to find out what it is. It’s more discomfort than anything else. We want to find out what it is so we can make him comfortable, so he can possibly help us down the road.”

Jordan, 25, went 0-3 with a 5.61 ERA in five major league starts this season. His fastball averaged 90 miles per hour, down from 92.3 in 2013. The Nationals sent him to Class AAA Syracuse when Fister came off the disabled in early May. Jordan made six starts in Class AAA, going 0-2 with a 4.06 ERA.

This season has paused Jordan’s rapid ascension. In 2013, Jordan rose from Class A Potomac to the majors, going 1-3 with a 3.66 ERA over nine start, using his impressive sinker to generate scores of groundballs.

Jordan broke his foot over the winter, a freak injury that happened while he was climbing out of a swimming pool. It required surgery, but healed in time for spring training, with a few minor, lingering effects.