Danny Espinosa's two-run double in the sixth inning put the Nationals on top for good as Washington downed the Tampa Bay Rays, 5-2, in the rubber match of a three-game interleague set.
Gio Gonzalez (9-3) allowed two runs on seven hits and two walks over six innings to earn the win for Washington, which took the last two games of this series on the heels of a four-game losing streak.
Tyler Clippard worked a perfect ninth to record his 11th save of the season.
Joel Peralta (0-3), pitching on appeal of an eight-game suspension handed to him Thursday, gave up Espinosa's go-ahead double to absorb the loss. Matt Moore started the game for Tampa Bay and allowed two runs on three hits and four walks with six strikeouts through five innings as the Rays lost for the sixth time in their last nine games.
The Rays left a man on second in the first inning, but were able to break through in the second after loading the bases with one out.
Following a Moore strike out, Desmond Jennings slapped a base hit through the right side of the infield to plate Hideki Matsui. Gonzalez fanned Carlos Pena to limit the damage and keep it a 1-0 game.
After the Nationals left the bases loaded in the bottom of the second, they managed to take the lead in the third, starting with Espinosa and Bryce Harper both walking to start the inning and moving up to second and third on a double steal.
Michael Morse's sacrifice fly to center field brought home Espinosa before Ian Desmond singled in Harper to give Washington a 2-1 edge.
Gonzalez limited the Rays to just a Jose Lobaton double in the fourth inning from there until Ben Zobrist led off the sixth with a double into the left- field corner and later scored on Sean Rodriguez's single up the middle to knot the game at two runs apiece.
But Washington quickly regained the lead in the home sixth with a two-out rally off Peralta when Jesus Flores doubled and pinch-hitter Adam LaRoche was intentionally walked before both rounded the bases on Espinosa's double down the first-base line.
"He hit the heck out of that ball," Nationals manager Davey Johnson said about Espinosa's double. "He's hitting the ball where it's pitched and he's hitting it awfully hard."
Tampa Bay had a chance to fight back again by filling the bags with two outs in the seventh inning, but Ryan Mattheus entered the game out of the bullpen and fanned pinch-hitter Will Rhymes to end the threat.
The Nationals made it a 5-2 game in the bottom of the seventh when Ryan Zimmerman singled, stole second and crossed the plate on Roger Bernadina's double to left field.
Sean Burnett and Clippard combined to retire the next six Rays batters to close out the victory.
"They're a good ball club. They have really good pitching. Their bullpen is really good," Rays manager Joe Maddon said.
Gonzalez has not allowed a home run in six straight starts...Tampa Bay leads the all-time series against the Nationals, 5-4. But the Rays are 10-11 against the franchise, having gone 5-7 against the Expos...Washington improved to 9-6 in interleague play this season, while Tampa Bay fell to 7-8...The Rays hit 3- for-13 with runners in scoring position and left 10 men on base...Washington went 3-for-10 with runners in scoring position and stranded eight...Peralta was ejected for having pine tar on his glove in Tuesday's game.