The NL East is becoming a walking infirmary. The latest: Nationals third baseman Ryan Zimmerman is headed for an MRI on his balky right shoulder.

For more, head over to Scott Miller's blog, as he's on site.

Zimmerman, 27, is hitting .224/.324/.345 with a homer and seven RBI through 68 plate appearances this season. He signed a six-year, $100 million contract extension this past offseason.

To this point the Nats haven't sorely missed Zimmerman's production, as they enter Tuesday night with a 12-4 record. Look for Chad Tracy to get most of the time at third base if Zimmerman is shelved for an extended period.

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