Voth will be recalled from Triple-A Fresno to start Sunday's game against the Braves, Sam Fortier of The Washington Post reports.
Joe Ross was tentatively set to make the start, but he was needed out of the bullpen Saturday. Voth joined the Nationals for Wednesday's doubleheader but did not pitch, and he'll make his season debut in the majors Sunday. The 26-year-old has a 4.40 ERA, 1.36 WHIP and 68:15 K:BB in 61.1 innings with Fresno and will likely be headed back to the minors after the outing.