Herz is scheduled to start Sunday's game against the Cardinals in St. Louis, Bobby Blanco of MASNSports.com reports.
Herz was optioned to Triple-A Rochester on July 8, though his demotion always looked to be the result of the Nationals wanting to maintain more flexibility with their active roster heading into the All-Star break. He rejoined the big club when a fifth starter was needed for the first time in the second half Tuesday and worked five innings in a loss to the Padres, giving up two runs on five hits and two walks while striking out four. Herz will take a 1-4 record and 4.95 ERA into his ninth start of the season with the Nationals on Sunday.