Blankenhorn elected free agency Monday after being outrighted off the Nationals' 40-man roster.
The Nationals outrighted Blankenhorn to Triple-A Rochester on Sunday.
The Nationals designated Blankenhorn for assignment Friday.
The Nationals optioned Blankenhorn to Triple-A Rochester on Tuesday.
Blankenhorn is out of the lineup for Wednesday's game against the Orioles, Mark Zuckerman of MASNSports.com reports.
Blankenhorn is out of the lineup for Friday's game against the Angels.
Blankenhorn is out of the lineup for Thursday's game against the Giants.
Blankenhorn is out of the lineup for Wednesday's game against the Giants.
Blankenhorn will serve as the Nationals' designated hitter and No. 6 batter in Sunday's game against the Brewers.
The Nationals reassigned Blankenhorn to minor-league camp Monday.