Nationals optioned OF Eury Perez to Triple-A Syracuse.
Nationals placed RHP Ryan Mattheus on the 15-day disabled list, retroactive to May 20, with a fractured right hand.
Matt Lindstrom has allowed an earned run in three of his last five relief appearances.
Pat Neshek owns a 2.81 ERA over 18 appearances.
Jonathan Herrera is batting .283/.327/.370 through 49 plate appearances.
Wesley Wright holds a 2.95 ERA over 21 appearances.
George Kottaras has just two hits this season.
Rex Brothers hasn't allowed a run since April 6.