Edwin Jackson took a one-hitter into the seventh inning, Adam LaRoche homered, and the Washington Nationals beat rookie Wei-Yin Chen and the Baltimore Orioles 3-1 on Saturday night.
Michael Morse had two hits and scored a run for the NL East-leading Nationals, who improved to 10-7 in interleague play and 2-3 against Baltimore.
Adam Jones hit his team-high 19th home run for the Orioles, whose six-game home winning streak ended.
Jackson (4-4) gave up one run, four hits and a walk in 6 1-3 innings. He retired the first 12 batters he faced and permitted only one runner past first base through six innings.
Sean Burnett worked the eighth, and Tyler Clippard got three straight outs for his 12th save in 13 tries.
Chen (7-3) allowed three runs, two earned, and six hits in five innings. The Taiwan native won his three previous starts, over Boston, Pittsburgh and Atlanta.