Ruiz was lifted from Wednesday's game against Atlanta in the fourth inning after taking a foul tip to the mask, Kyle Williams of TheBanner.com reports.
Ruiz has a history of concussions, so this is a worrisome development. The Nationals should have more on his status after the game. Ruiz flew out in his lone plate appearance Wednesday before exiting. He was replaced by Harry Ford, who would stand to benefit if Ruiz needs to miss additional time.