WASHINGTON -- It was bound to end at some point, both Wei-Yin Chen's stretch of strong starts and the Orioles' road winning ways.
Staked to an early three-run lead, the rookie left-hander could not sustain his good fortune on Sunday afternoon, allowing a season-high six earned runs in his shortest start as a big leaguer. After initial success against Nationals starter Stephen Strasburg, the Orioles' lineup could not pull out another win away from Camden Yards nor prevent Chen from his first loss, as Baltimore dropped the Beltway Series finale, 9-3, at Nationals Park.
With a win, Chen (4-1) would have been the first starting pitcher since 1997 to begin his Orioles career 5-0. Instead, the team's road winning streak ended at nine games after Chen surrendered three runs in the third, two in the fourth on back-to-back two-out home runs and a single score in the fifth. The second home run came off the bat of Strasburg and marked the first time this season Chen had allowed two long balls in a game.
"This is baseball. Sometimes you have a good day, sometimes you have a bad day," Chen said through an interpreter. "Definitely, I had a terrible start today."
Chen also tweaked his non-throwing wrist, though he didn't seem too concerned about it.
"When I swing, it hurts, but it didn't bother me throwing pitches," he said. "It's not a big deal, I just need a couple of days rest."
Xavier Avery finished 2-for-4 with an RBI, a run and his first career stolen base, but the Orioles struck out eight times in five innings against Strasburg (4-1). After picking up four hits en route to a 3-0 lead through two frames, Baltimore didn't register another until the ninth before the crowd of 41,918.
"We won the series. We're happy about that," said Adam Jones, focusing on the big picture before breaking down how the Nationals starter wore down the Orioles' hitters. "Strasburg, he got in a groove. Any pitcher who gets in a groove is going to be comfortable, and they came back and gave him some run support and allowed him to get out there and be comfortable."
Struggling with offspeed pitches and suspect command, Chen lasted only 4 1/3 innings, allowing eight hits and three walks with five strikeouts.
"He made a lot of mistakes with his breaking ball today," Orioles manager Buck Showalter remarked. "That was pretty much the difference."
After avoiding damage when two runners reached in the first and tossing a 1-2-3 second, the 26-year-old Taiwanese hurler's troubles began in the third. It started with a Strasburg leadoff single, a Danny Espinosa double and Bryce Harper's two-run triple. The tailing liner squirted out of the glove of a diving Nick Markakis, allowing both runners to score. Harper crossed home plate with the tying run when the Orioles could not turn Ian Desmond's grounder into an inning-ending double play.
The Orioles lost the lead for the first time in the series with two outs in the fourth, as Nationals catcher Jesus Flores homered to right field. Up stepped Strasburg, who parked an 0-2 curveball from Chen over the wall in left-center for his first career home run.
"In Japan, pitchers can hit," Chen said. "But I just realized pitchers can hit here, and I made a big mistake here and threw a bad pitch."
Desmond's RBI single in the fifth scored Harper and put the Orioles in a 6-3 hole.
Avery opened the game with a single, took second on J.J. Hardy's warning track fly ball out to center field and came home on Markakis' base hit to right. After his 0-for-4 Major League debut, Avery has reached base in seven straight games.
In the second, the 19-year-old Harper ranged from his spot in center field to the left-center gap in time to catch Wilson Betemit's fly ball. He didn't. The drop allowed Betemit to reach second, who then went to third on Chris Davis' slow rolling infield single before scoring on Robert Andino's RBI groundout. Davis came home from third base on Avery's second hit in two innings.
Espinosa tacked on a two-run homer in the eighth off Orioles reliever Dana Eveland.
"It was a lot of fun," Espinosa said of the first meeting between the neighboring clubs in which both teams have a winning record. "When you're playing for first place in your division, it's more exciting."
Adam Jones extended his hitting streak to 12 games with a single in the ninth.
That streak survived, the road-winning version died. Still, a 4-1 road trip, that's good living.
Ben Standig is a contributor to MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.