The Nationals selected Lile's contract from Triple-A Rochester on Friday.
Lile began the season at Double-A Harrisburg before being promoted to Rochester in late April. Between the two stops, the 22-year-old has slashed .337/.383/.509 with three long balls and nine stolen bases over 39 contests. Lile should see some starts in the outfield against righties while Dylan Crews (oblique) and Jacob Young (shoulder) are out. Robert Hassell and Alex Call will also be in the mix for playing time in those two spots.