The scoring started in the first inning against O's right-hander Bud Norris. With Final Vote candidate Anthony Rendon on second, Werth doubled to right field to score the first run. Adam LaRoche followed and singled to right field to make it a 2-0 game.
Right-hander Doug Fister took advantage of the situation and won his team-leading eighth game. He lasted seven innings, allowed two runs on seven hits, struck out three and threw 113 pitches. The Orioles scored in the first inning on an RBI single by Chris Davis, and their second run came on a home run by Manny Machado in the fourth inning.
"Doug continues to battle," Nationals manager Matt Williams said. "We stretch him out. We sent him back out there with the notion that if he got in trouble, we'll go get him. He really found the zone the last inning, especially. He pitched really well."
Fister was reluctant to talk about himself. Instead, he focused on the team victory.
"The guys play very well. The offense came out swinging. We swung the bats well," Fister said. "Great plays on defense. Guys are playing well together. We are getting some momentum together. That's kind of where we are at. It's good going into the break."
While the O's got two runs, it was mostly the Nationals doing damage. In the second inning, Wilson Ramos made it 3-1 when he homered into the left-field stands. Two innings later, Ian Desmond hit his 16th homer, a solo shot over the right-center-field wall.
With Brad Brach on the mound in the fifth, Danny Espinosa scored on a sacrifice fly by LaRoche. In the seventh, Werth hit his ninth home run, a solo shot into the left-field stands.
"It's good to give Doug some run support," Werth said. "He is great to play defense behind. He works fine. You give him some runs and let him do his thing. Good win."
The Orioles had a chance to get back in the game in the sixth inning. Baltimore had runners on first and third with one out, but Rendon made the defensive play of the game at third base. Caleb Joseph hit a shot to Rendon, who picked the ball and started the inning-ending double play.
"Their third baseman had a great night playing third base," Baltimore manager Buck Showalter said about Rendon. "We could have got back in it a little bit, but they didn't let us defensively."
LaRoche is impressed by how Rendon is able to play both second and third base without skipping a beat.
"As athletic as he is, it's a little bit easier. It would be tough on a lot of guys," LaRoche said. "Again, he is comfortable at those spots and he can handle the job wherever he is at."
With the win, the Nationals are 49-40.