With the score tied 3-3 in the eighth, Michael Young drew a one-out walk from Drew Storen (0-1). One out later, Delmon Young sent a grounder down the right-field line, allowing him to score all the way from first on the single.
Michael Martinez came in to pinch-run for Delmon Young and added an insurance tally on Domonic Brown's two-bagger as the Phillies evened the three-game series.
Brown also smacked a solo homer and Erik Kratz added a bases-empty shot for Philadelphia.
Adam LaRoche went 2-for-4 with a solo homer and two RBI for the Nationals.
'SNL': 'Anchorman 2' cast, One Direction sing 'Afternoon Delight' [VIDEO]
Selena Gomez drops F-bomb, walks off stage during Jingle Ball performance