Nationals center fielder Rick Ankiel will begin a rehab assignment in Class AA Harrisburg today, a sign that he’s close to coming off the disabled list with a sprained right wrist and could potentially replace first baseman Adam LaRoche on the 25-man roster.

LaRoche did not travel with the team to Milwaukee, instead seeing a doctor to receive tests on his left shoulder. LaRoche has played with a slight tear in his labrum all year, a likely contributor to his .172/.288/.258 batting line to start his first season with the Nationals.

If LaRoche winds up on the disabled list – a likely development – then Michael Morse will likely receive the majority of playing time at first base. Ankiel would provide an outfielder to replace Morse on the roster. The Ankiel-for-Morse outfield swap could lead to awkward roster composition, since Ankiel, Laynce Nix and Roger Bernadina are all left-handed and would be splitting the center field and left field spots.