Voth was optioned to Double-A Harrisburg on Saturday, Brittany Ghiroli of The Athletic reports.
Voth is the roster casualty to make room for Max Scherzer's return from the paternity list as he won't be needed to pitch again before the All-Star break. He could remain in the minors for some time as the Nationals won't need a fifth starter until July 20 against the Braves.