Demny pitched five innings and combined with two relievers on a one-hitter as the Class A Advanced Nationals blanked Salem, 2-0, to earn a split of their doubleheader.
A sixth-round pick by Washington in the 2008 Draft, Demny was perfect until he issued a two-out walk to Daniel Butler in the fourth inning. He retired Shannon Wilkerson on fly ball to right field to end the inning.
After David Mailman grounded out leading off the fifth, Demny (4-6) walked Zach Gentile. Michael Almanzar ended the no-hit bid with a double to left field, but the 21-year-old right-hander preserved the shutout by getting Derrik Gibson to pop up to shortstop and striking out James Kang.
Demny, who fanned five, lowered his ERA to 4.06 in 13 Carolina League starts. He's won three of his last four starts after losing three in a row. Command has been an issue for the 6-foot-2 Texan, who's walked 33 batters over 68 2/3 innings.
Josh Smoker came on in the sixth for Potomac but hit and walked the first two batters he faced. Joe Testa bailed him out, coaxing Shannon Wilkerson into an inning-ending double play, then worked a perfect seventh for his first save.
Eury Perez drove in both runs with a single in the second, finishing 2-for-3. Jeff Kobernus also had two hits and registered his league-leading 27th and 28th stolen bases.
Former first-round pick Anthony Ranaudo (1-3) took the loss, despite allowing two runs on five hits and fanning five over five innings. After going 4-1 with a 3.33 ERA in 10 starts with Class A Greenville, the LSU product has a 2.78 ERA in four Carolina League starts.