Updated

Philadelphia, PA (SportsNetwork.com) - Yunel Escobar and Clint Robinson each scored during the 10th inning and the Washington Nationals avoided a three- game series sweep with a 4-3 win over the Philadelphia Phillies on Sunday.

Wilson Ramos drove in two runs, Bryce Harper homered and Robinson finished with three hits for the Nationals, who had dropped their previous five games at Citizens Bank Park

Aaron Barrett (1-0) earned the win after striking out two in a scoreless ninth, while starter Max Scherzer surrendered just one run on six hits and two walks with eight strikeouts over six innings.

"It's a big win for us," Washington manager Matt Williams said. "Max pitched really well again. It's good for us to come through late."

Cody Asche went 3-for-4 with an RBI and Darin Ruf homered for the Phillies, who were coming off a 3-2 win Saturday night thanks to Odubel Herrera's walk- off hit during the bottom of the 10th inning.

Philadelphia starter Sean O'Sullivan, who was brought up from Triple-A Lehigh Valley prior to the game, gave up two runs on five hits and a walk with five strikeouts in six frames.

"O'Sullivan gave us a big lift today with his outing," Phillies manager Ryne Sandberg said. "Hard-fought game right down to the last out."

Escobar led off the 10th inning with a double on a sharp grounder down the right-field line off Jake Diekman (0-1), took third on Harper's groundout and hustled home on Justin De Fratus' wild pitch. Robinson doubled off the center- field wall and came home on Ramos' liner just past the glove of shortstop Freddy Galvis into left.

Drew Storen came on to pitch the bottom half and walked Galvis and Asche to begin the frame. Herrera brought the Phillies within one three batters later with an infield single, but Storen got Cesar Hernandez to ground out for his second save of the season.

With two outs in the first inning, Harper crushed a first-pitch sinker into the flower bed in left-center field to give Washington an early 1-0 lead.

The Nationals increased their lead in the fourth after Ryan Zimmerman and Robinson singled to place runners on the corners. Ramos drove in Zimmerman with a sacrifice fly to right field.

Philadelphia sliced its deficit in half during the fifth. O'Sullivan worked a one-out walk and Revere singled to right. Two batters later, Asche's line drive dropped in front of Harper in right field, scoring O'Sullivan. Ben Revere advanced to third and Asche moved to second on Harper's throw home, but Ryan Howard struck out to end the threat.

Ruf opened the seventh by crushing a fastball to deep left field, tying the game at 2-2.

Game Notes

O'Sullivan's last major-league win came as a member of the Royals in an 11-5 win over the Yankees on May 12, 2011 ... Scherzer registered his first hit since Aug. 24, 2013 against the Mets when he played for the Tigers ... Howard struck out four times ... The Phillies travel to Citi Field Monday to start a three-game series against the Mets, while the Nationals begin a three-game set in Boston on Monday.