BALTIMORE — The Orioles' evolving rivalry with their neighbors down Interstate 95, the Washington Nationals, packed a little extra punch this week for the simple fact that both entered the series as legitimate postseason contenders. They entered Thursday's game atop their respective division, with nearly identical records.
And while the Orioles will have to wait until August for the opportunity to claim true "Beltway Series" bragging rights, they took two of three against the Nationals this week after their 4-3 win Thursday night before an announced 30,417 at Camden Yards. Tuesday's rained-out game in Washington will be made up Aug. 4.
The Orioles (50-41) have reached the 50-win mark in their 91st game, the earliest since their wire-to-wire division-winning season of 1997. The club reached 50 wins in 92 games last season and in 94 in their 2012 playoff season.
The Orioles also extended their American League East lead to three games over the Toronto Blue Jays, who were off Thursday.
Despite facing the minimum number of hitters his first time through the batting order, left-hander Wei-Yin Chen - who had allowed three or fewer runs in six of his past seven starts - fell one out shy of a quality start, allowing three runs on eight hits over 5 2/3 innings. Still, he won his team-high ninth game.
The Orioles' bullpen protected the one-run lead it inherited, but not without its tense moments.
Right-hander Darren O'Day, whose 1.13 ERA entering the game was the lowest among AL relievers, worked his way out of his own two-out, bases-loaded jam in the eighth inning.
With the Orioles clinging to a 4-3 lead, Adam LaRoche hit a one-out double off O'Day, and after a strikeout of Ryan Zimmerman, he intentionally walked Bryce Harper with first base open.
But a passed ball put both base runners in scoring position, and O'Day's 3-2 pitch to shortstop Ian Desmond hit him, loading the bases.
O'Day recovered, recording his ninth consecutive scoreless outing by inducing a inning-ending flyout to center from Wilson Ramos. Closer Zach Britton then converted his 15th save in 17 opportunities.
The Orioles took a 4-0 lead on Nationals left-hander Gio Gonzalez, scoring three runs in the third inning, all with two outs.
Left fielder Steve Pearce put the Orioles up only two batters into the bottom of the first inning with his 11th homer of the season, taking a 2-0 fastball into the left-field seats.
After Gonzalez retired the first two batters in the third, leadoff hitter Nick Markakis drew a walk, Pearce singled and Adam Jones flared an RBI double down the right-field line to place runners at second and third.
Nelson Cruz then hit a grounder up the middle that Desmond gloved at the edge of the grass. But instead of getting the out at first, Desmond spun around and threw to third.
His throw sailed wide, allowing Pearce and Jones to score and giving the Orioles a 4-0 lead.
Gonzalez (6-5) limited the damage after that, going 6 2/3 innings and yielding four runs, three of them earned, on six hits over 6 2/3 innings. He struck out seven batters and walked three.
The Nationals (49-41) scored their first run on Ryan Zimmerman's two-out RBI single in the fourth, a hit that came only after Washington had extended the inning on a replay challenge.
With one on and two outs, Chen (9-3) delivered an 0-1 pitch that sailed in on Adam LaRoche and initially was called a ball. But Nationals manager Matt Williams challenged the call, and replays showed the pitch had grazed the front of LaRoche's jersey.
After a 58-second review, LaRoche was awarded first base, placing runners at first and second. Zimmerman singled to center to score one run, and both base runners moved into scoring position on Jones' throw home.
Chen, who struck out six batters and walked none on the night, then won possibly the most important at-bat of the night, striking out Bryce Harper on a called strike three after falling behind Harper 2-0, ending the inning.
Jayson Werth hit his 10th homer of the season on a 77-mph hanging curveball to open the sixth, the eighth homer Chen has allowed over his past five starts.
Chen wouldn't last the inning, allowing a one-out double to Zimmerman. Desmond followed with an RBI double off the right-field scoreboard that scored Zimmerman and chased Chen from the game.