Zimmerman (foot) will begin a rehab assignment with Double-A Harrisburg on Friday, Mark Zuckerman of MASN Sports reports.

EDGE Analysis

Manager Dave Martinez said last week that Zimmerman would be activated "soon," but the tail end of his recovery apparently didn't move as quickly as expected. The 34-year-old has been sidelined due to plantar fasciitis since July 21 and should be ready to rejoin the Nationals after a handful of games in the minors.