(Julio Cortez/AP)

Mattheus visited a specialist this morning in Baltimore to diagnose the severity of the plantar fasciitis in his left foot. Mattheus had been feeling pain for about two weeks, and yesterday he aggravated it while jogging in the outfield before the game. Mattheus said last night he expected to miss about two weeks. He is eligible to return June 5.

For now, the Nationals will use Wang in relief. He was scheduled to arrive with the team today, anyway, and throw a side session. It is unclear if he will be available for tonight’s game.

Wang last pitched in a rehab start Saturday for Class AAA Syracuse, throwing 5 2/3 innings while allowing four runs. Wang made a month’s worth of rehab appearance in returing from a hamstring injury he sustained March 15 covering first base in a spring training start.

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