WASHINGTON (AP) -- Despite winning two of the three games in the series, the New York Mets still left Washington with a little bit of an empty feeling.
Jayson Werth's two-out RBI double in the eighth inning capped a late rally and the Washington Nationals avoided a series sweep with a 6-5 win over the Mets on Sunday night.
The Mets led 5-2 in the seventh, but the Nationals scored once in that inning on Wilson Ramos' run-scoring single and added three in the eighth.
"Anytime you can win a series, it's big," Mets manager Terry Collins said. "This time of the year, you've got to win as many as you can.
"Certainly, this is one we're going to look back on and kick ourselves a little bit for letting it get away. But yeah, winning a series is big."
Starter Jonathon Niese never had a 1-2-3 inning, but the Nationals managed only single runs in the second and fourth against him. He allowed two runs and 10 hits in 5 2-3 innings before leaving with a left leg cramp.
The left-hander also left with the lead, poised for his fourth win in five starts.
Scott Atchison replaced Niese with two outs in the sixth and stranded two inherited runners. Ramos' RBI single against Atchison in the seventh made it 5-3.
Gonzalez Germen (1-2) allowed one run after Scott Rice gave up two in the eighth.
"A lot of things didn't go our way tonight," Niese said. "A lot of broken-bat hits, ground ball hits that got through the hole. And that's kind of how it goes sometimes, a game can unravel in a hurry."
Daniel Murphy and Lucas Duda each drove in two runs, and Matt de Dekker smacked his first career home run for the Mets. New York last swept a series from Washington May 25-27, 2009.
Rice entered in the eighth with the Mets leading 5-3. Rice, New York's third pitcher, allowed consecutive singles including Denard Span's pinch-hit single which extended the outfielder's hitting streak to 15 games.
After Bryce Harper sacrificed the runners to second and third, Scott Hairston scored on Anthony Rendon's groundout and Span came around on Ryan Zimmerman's infield single.
Werth's second double of the game scored Zimmerman from first base and was one of Washington's 16 hits.
"We finally got some hits with runners out there," Nationals manager Davey Johnson said. "It took a while."
Recalled from Triple-A Syracuse before the game, reliever Erik Davis (1-0) pitched a scoreless eighth.
Rafael Soriano, Washington's sixth pitcher, finished the Mets off in the ninth for his 36th save.
Murphy's hot hitting stretch continued with an RBI double in the first inning and a two-out run-scoring single in the fifth against Ross Ohlendorf. The second baseman has 11 hits in his past 19 at-bats.
The Mets had 30 hits during the past two games. Murphy, Duda, den Dekker and Eric Young each had two in the series finale.
Murphy followed Young's leadoff double with a two-base hit for New York's first run and scored one out later on Duda's single.
Another RBI single from Duda, who started for the injured Ike Davis at first base, made it 5-2 in the seventh.
As for his injured pitcher, Collins said of Niese, "No issue with the leg. I'm just glad, I thought it was the knee. He's OK."
"It's that kind of year," Niese said of New York's string of injuries this season. "Today was tough, it was so humid. I was crushing Gatorades and waters, and still cramping up."
New York went ahead 3-0 as de Dekker's first major league home run landed in the second deck of the right-center field stands.
Nationals starter Ross Ohlendorf pitched five innings, allowing four runs and nine hits. He had a 2.82 ERA in four previous starts this season.
Notes: The Mets, with their rotation depleted by injuries, have signed RHP Aaron Harang to a minor league contract and assigned him to Triple-A Las Vegas of the Pacific Coast League. Harang was 5-11 with a 5.76 ERA in 22 starts this year for the Seattle Mariners. Overall, he has pitched 12 years in the majors, going 110-115 with a 4.29 ERA. ... The Mets also called up three players, including RHP Vic Black, who was acquired on Aug. 27 from the Pirates in a deal that sent OF Marlon Byrd and C John Buck to Pittsburgh. ... RHP Daisuke Matsuzaka (0-2, 8.68 ERA) opposes Paul Maholm (9-10, 4.37) as New York opens a three-game series at Atlanta on Monday.
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