BALTIMORE (AP) -- Trey Mancini capped a three-homer binge in the first inning against Gio Gonzalez, and the Baltimore Orioles beat the Washington Nationals 6-4 on Monday night for their season-high fifth straight victory.
Kevin Gausman (2-3) limited baseball's most potent offense to two runs over seven innings. He retired the first 10 batters and struck out eight in his longest outing of the year.
Joey Rickard hit a leadoff homer and Mark Trumbo added a solo shot before Mancini connected with a runner on to make it 4-0. That was enough offense for the Orioles, who now hold a 37-24 advantage over their neighboring rivals in the so-called "Beltway Series," which began in 2006.
Caleb Joseph had a career high-tying four hits for the Orioles. Baltimore (21-10) owns the second-best record in the majors behind the AL East-leading New York Yankees.
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Bryce Harper homered and drove in two runs for the Nationals, who lead the majors in runs, hits and batting average
After the Orioles let a six-run cushion shrink to three, Brad Brach worked the ninth for his eighth save. After Brach gave up a one-out RBI double to former Oriole Matt Wieters, pinch-runner Trea Turner strayed too far from second base on a groundout to first and the game ended with a rundown in which Adam Lind was tagged out between third and home.
Gonzalez (3-1) came in with a National League-leading 1.64 ERA for the team with the best record in the NL. None of that mattered to Baltimore, which took the lead for good when Rickard sent the left-hander's fourth pitch into the left-field seats.
Gonzalez made it through six innings and gave up six runs -- one fewer than his previous six starts combined. His poor outing upped his ERA to 2.64 and dropped his career record against Baltimore to 1-6.
The Washington Nationals announced Friday Dusty Baker will not return as manager of the club in 2018.
Baker led the team to the first back-to-back division titles in franchise history, and the Nationals were 192-132 under Baker, but they failed to make it to an NLCS.
Baker is 14th in MLB history with 1,863 career wins.
The next Nationals' manager will be their seventh since they arrived in DC.
Only the Marlins have had as many.
"I'm surprised and disappointed," Baker told USA TODAY Sports. "They told me they would get back to me and I told them I was leaving town yesterday and they waited 10 days to tell me."
"I really thought this was my best year. We won at least 95 games each year and won the division back to back years but they said they wanted to go a different direction. It's hard to understand."
The team also announced the contracts for the Major League coaching staff have also expired, and the search for a new manager will begin immediately.
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While Nats fans were still digesting the news that Dusty Baker will not return as manager next year, the team released some more surprising news.
Second baseman Daniel Murphy underwent knee surgery today, per an official team report.
Washington Post reporter Chelsea Janes reported that the surgery is considered significant and the team won't put a timeline on the recovery process:
"The procedure, according to the statement released by the team, repaired articular cartilage in Murphy’s right knee. For those interested in the details, it was a debridement and microfracture surgery, and orthopedic surgeon Timothy Kremchek performed it."
"For those concerned with the implications of the procedure, those are still unclear. The statement clarified that Murphy’s rehab “will progress throughout the offseason,” as one would hope, and did not include a timetable.
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