PHILADELPHIA -- Ryan Zimmerman delivered a go-ahead RBI single in the top of the 10th inning to help lift the Washington Nationals to a 5-3 win over the Philadelphia Phillies on Saturday night at Citizens Bank Park.
With runners on first and second and two outs, Zimmerman, buried in an 0-2 count, laced an 100 mph fastball from reliever Jake Diekman into center field to score center fielder Denard Span, who walked to lead off the inning.
The Nationals then made it 5-3 when right fielder Jayson Werth scored on a wild pitch by Diekman.
The win kept the Nationals (50-42) tied for first place atop the National League East with the Atlanta Braves (51-43).
The Phillies (42-52), who were 2-for-14 with runners in scoring position, had their five-game winning streak snapped.
Diekman (3-3), who took the loss, was ejected after the top of 10th inning by home plate umpire Andy Fletcher. Reliever Ross Detwiler (1-2) picked up the win with a scoreless ninth inning.
Closer Rafael Soriano posted his 22nd save by striking out the side in the 10th.
With the Phillies trailing 3-2 in the bottom of the eighth inning, Ben Revere slapped a tying two-out single up the middle off reliever Tyler Clippard to set up extra innings.
A marquee pitching matchup featuring Washington's Stephen Strasburg against Philadelphia's Cole Hamels turned into a subplot.
Strasburg allowed two runs in 5 2/3 innings while throwing a season-high-tying 111 pitches and striking out nine to boost his NL-best strikeout total to 149.
Hamels delivered his 37th quality start since 2013 -- sixth most in the majors during that span -- with seven innings of three-run ball and striking out five with three walks.
Werth went 1-for-4 with a homer and three RBIs.
After Hamels had retired 12 of 13 batters since the second inning, second baseman Anthony Rendon started the sixth inning with a walk and Werth belted a two-run homer to stretch the Nationals' one-run lead to 3-0.
Phillies right fielder Marlon Byrd cut into the Nationals' lead with a two-run single in the sixth inning. Shortstop Jimmy Rollins and second baseman Chase Utley hit back-to-back singles to begin the inning before moving up to second and third on a double steal.
The Nationals led off the game with a walk and double to force Hamels into early trouble.
Hamels, however, prevented the first inning from getting out of hand by yielding only one run on Werth's RBI groundout.
With a runner on third and two out, third baseman Cody Asche made a sparkling play diving to his left and throwing out third baseman Ryan Zimmerman to end the inning.
Philadelphia threatened in the first and second innings but could not capitalize.
In the first, Strasburg stranded a runner on third with one out by striking out Utley and first baseman Ryan Howard.
Then in the second, Strasburg scattered three hits and had two strikeouts, plus the help of catcher Wilson Ramos throwing out Byrd attempting to steal second base.
Eight of Strasburg's first 15 outs were strikeouts.
NOTES: Phillies LF Domonic Brown was scratched from Saturday's starting lineup around 4 p.m. because of an illness. OF Ben Revere started in his place and played center field, and Grady Sizemore moved from center field to left field. ... Nationals RHP Jordan Zimmermann (biceps cramp) underwent an MRI exam on Saturday. Washington manager Matt Williams said the team was still awaiting the results. Zimmermann left Friday night's start after 3 1/3 innings because of the injury. ... Phillies C Carlos Ruiz (concussion) will head to Clearwater, Fla., on Sunday to ramp up his rehab process with batting practice and work on blocking balls. Ruiz, who has been out since June 26, probably will begin his rehab assignment on July 18.