WASHINGTON -- The Nationals keep rallying in the late innings.
Washington became the first team win four in a row when trailing by two runs in the seventh inning or later in all four since the New York Giants against the Boston Braves and Philadelphia Phillies from June 25-28, 1923, according to the Elias Sports Bureau.
"The main thing that they can get out of this is that you don't never give up," Nationals manager Frank Robinson said. "As long as you have an out left, you have a chance to win a ballgame. That's a good lesson for a young ballclub."
Kearns wanted to play Sunday despite going 20 innings in Saturday's doubleheader with a tight right groin.
"I'm fine," said Kearns, who has 13 RBI in his last 13 games. "I told Frank I was fine. It's nothing where I felt like I couldn't play."
Arizona dropped to 0-6 at RFK Stadium and at 64-72 fell eight games below .500 for the first time this season.
Brandon Webb (14-6) had a 3-1 lead and had retired 19 of 20 batters, including 13 in a row, before Nook Logan reached on a bunt single leading off the eighth. Pinch-hitter Ryan Church walked, and Felipe Lopez and Ryan Zimmerman hit consecutive RBI singles.
Nick Johnson was intentionally walked, and Kearns hit a 3-2 pitch to deep right-center, chasing Webb.
"I felt good," Webb said. "That is the way it is going for the whole team. Bad luck."
Webb struck out eight.
"Webby did all he could do, except for the last pitch," Arizona manager Bob Melvin said. "He was a little spotty in the first inning, but really good after that."
Ryan Wagner (3-2) pitched 1 2/3 innings, and Jon Rauch pitched a perfect ninth for his first career major league save. Nationals closer Chad Cordero was given the day off after pitching three innings in Saturday's doubleheader.
"I think it's real big for the team," Rauch said. "To get a sweep, especially the way we've been playing and all that's been going, it's a great thing."
Nationals starter Tony Armas Jr. gave up three runs, four hits and four walks in 6 1/3 innings, his longest outing since a seven-inning no-decision on Aug. 13.
Kearns hit an RBI single in the first, but Arizona built its lead on Chad Tracy's fifth-inning homer, Conor Jackson's sixth-inning sacrifice fly and Orlando Hudson's seventh-inning RBI single. Hudson's hit drove in Carlos Quentin, who sprinted home from second and slipped a hand on the plate underneath Brian Schneider's tag.
- Alfonso Soriano stole his 36th base as he closes in on joining Jose Canseco, Alex Rodriguez and Barry Bonds as the fourth member of baseball's 40-home run, 40-stolen base club. Soriano has 44 homers.
- Tracy's home run was his 16th but his first since July 31.
- Logan is 3-for-8 since he was acquired from Detroit on Friday, where he played most recently with Double-A Erie. The center fielder also robbed Stephen Drew of an extra-base hit with a sprawling catch in the third inning.
- Webb has allowed 16 earned runs in his last four starts, going 1-2.