Manager Matt Williams said Tuesday that McLouth will have surgery Thursday for a torn labrum and is expected to recover in time for spring training.
Williams says McLouth has had discomfort in his throwing shoulder all season. The symptoms worsened after he dove for a ball in Miami in late July.
McLouth last played Aug. 1 and is on the 15-day disabled list. He is in his first season with the Nationals and hit .173 with one home run and seven RBIs in 79 games.
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