WASHINGTON (AP) -- Neither Charlie Manuel nor Jimmy Rollins can remember a stretch quite like the one Philadelphia is enduring now.
Stephen Strasburg pitched a four-hitter and struck out 10 in the first complete game of his career, Jayson Werth had his second straight three-hit game and the Washington Nationals completed a three-game sweep with a 6-0 victory over the Phillies on Sunday night.
Outscored 23-7 over the weekend, Philadelphia has lost 17 of 20. The Phillies never had a runner in scoring position during their 11th straight road loss.
"It's been tough," Manuel said. "Since I've been managing in the major leagues, this is definitely the toughest stretch we've ever had."
The sweep denied Manuel the 1,000th win of his managing career.
At 52-65, the Phillies are three games behind the third-place Mets in the NL East and open a three-game series Monday in Atlanta.
"I'd have to go back and look, but I don't think I've ever had a stretch like this either," shortstop Rollins said. "We've had some stretches where we lost some games in a row, but we'd find a way to put some wins in a row right after that. But it isn't happening right now."
Kevin Frandsen had two of the Phillies' four hits.
Philadelphia had not been swept by the Nationals-Expos franchise in a series of three games or more since losing a four-game series from August 25-28, 2003, while in Montreal.
"Some games we're losing we're getting outplayed, but some games we're not making the right plays," Rollins said.
"We're not making pitches, we're not getting the hits, and that makes it very tough when you're out there playing and you're battling and you hope to come up with the big hit. Sometimes you will, sometimes you won't. We haven't at all."
Strasburg (6-9) dominated the reeling Phillies for his first win since July 7 against San Diego. The Nationals had lost five straight games started by the right-hander.
"He'd get ahead of us with either his fastball or his breaking ball. He's tough," Manuel said. "His breaking ball really set up his fastball later in the middle innings until the end of the game. He was good. Power when he wanted it."
Washington scored two runs in the fourth and three in the fifth against Kyle Kendrick (10-9), who surrendered 11 hits -- all singles -- over 5 1-3 innings. Making his fourth start against the Nationals this season, Kendrick allowed six runs, four earned.
He's 3-5 in his last eight starts with a 7.07 ERA.
"It's just been frustrating the last few starts for me," Kendrick said.
Werth, who had a go-ahead, two-run homer among his three hits Saturday, delivered an RBI single in the first inning to give Washington a 1-0 lead.
Steve Lombardozzi also had three hits, including an RBI single.
In between wins, Strasburg went 0-3 with 4.93 ERA in five starts. Two of Strasburg's six victories on the season have come against the Phillies.
Strasburg's biggest stress came starting the second inning. He winced after throwing a second straight ball to Domonic Brown, leading to a visit from the Nationals' training staff.
After walking Brown on four pitches -- the only walk he issued -- Strasburg struck out Darin Ruf and Cody Asche on his way to retiring 14 of the next 15 batters. The right-hander has allowed two or fewer runs in 11 of 13 home starts.
"It felt good," Strasburg said of finishing the game. "It's something that you try and do every time out. I've learned how to go out there and get outs with less pitches."
Wilson Ramos and Denard Span each had RBI singles in the fourth inning.
Chase Utley's throwing error in the fifth allowed two runners to score. Lombardozzi tacked on an RBI single for the Nationals' third run of the inning.
Notes: Philadelphia's last road win came July 19 at Cincinnati in its first game after the All-Star break. ... Brown has a six-game hitting streak. . The Phillies' road trip continues at Atlanta on Monday with LHP Cole Hamels (4-13, 3.81 ERA) facing RHP Julio Teheran (9-5, 2.96).
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