Matt Wieters crushed the go-ahead two-run home run in the bottom of the eighth inning, and the Baltimore Orioles edged the Washington Nationals, 2-1, in the rubber match of the Beltway Series at Camden Yards.

Pedro Strop (4-2) picked up the win after getting the final out in the top of the eighth. Jim Johnson notched his 22nd save of the season with a scoreless ninth for the O's, who had lost four of five coming in.

"I think every hitter in our lineup is going out there believing they are going to get a hit," Wieters said. "Every hitter believes they are going to come up with that big hit, and that's how you're going to win games."

Baltimore starter Jake Arrieta pitched well in six innings, allowing one run on five hits with five strikeouts and walk.

Ryan Zimmerman knocked in the only Washington run with an RBI single and Bryce Harper added a pair of hits for the Nats in defeat.

Sean Burnett (0-1) suffered the loss after allowing Wieters' long ball. Starter Ross Detwiler tossed five scoreless innings and allowed four hits and two walks with three strikeouts, but had to settle for the no-decision.

"We play a lot of close games and our bullpen expects to get the job done," Burnett said. "We've done a great job most of the year but today I let one slip away."

Trailing, 1-0, after seven innings, the O's finally got a clutch hit in the eighth after failing to come up with one on several occasions earlier in the game. Adam Jones got on base with a solid single into right to begin the frame and Wieters followed by taking a sinker out over the plate from Burnett deep and into the Orioles' bullpen in left field, putting them ahead for good.

Johnson got Michael Morse to ground out to start the ninth inning, but walked Ian Desmond to put the tying run on the base paths. Johnson then fanned Danny Espinosa and Wieters wrapped up the win for Baltimore by cutting down Desmond trying to steal second base.

Earlier, Washington broke a scoreless tie in the third when Jhonatan Solano ripped a double down the line in right to start the inning and came around to score on a base hit to left by Zimmerman.

J.J Hardy began the Baltimore fourth with a single, Wieters slapped one into left two batters later, and Steve Pearce walked to load the bags with two outs for Ronny Paulino. Detwlier fought back and got Paulino to fly out to left to end the inning.

Robert Andino ripped a single to right and Brian Roberts drew a walk in the Baltimore fifth and both runners advanced on a groundout by Hardy, but the O's again failed to score as Jones flew out to left to end the frame.

The Orioles again wasted a chance to score in the seventh when Paulino singled and Andino walked before both runners moved up on a Roberts groundout, but Hardy grounded out to third to strand both runners.

Game Notes

The Orioles improved to 11-7 in interleague play this season and 5-1 in six interleague series...In four career starts against the Nats, Arrieta is 0-1, but the O's are 3-1 in those games...Baltimore went 0-for-6 with runners in scoring position and left eight men on base, while Washington was 1-for-5 with RISP and stranded six...The O's improved to 13-6 in one-run games this year.