WASHINGTON -- Chicago Cubs catcher David Ross struck out three times in Thursday night's series opener against the Washington Nationals.

And yet he might have been the most important player in the Cubs' 2-1 victory.

Ross caught two runners stealing, then picked pinch hitter Clint Robinson off of first base for the game's final out as the Cubs moved to 2-2 on their nine-game road trip.

"He does so many good things on the field that you cannot overlook that and just reduce it to three strikeouts," said Cubs manager Joe Maddon. "I really wanted him in the game late today. I thought he had a great feel for the game."

Jake Arrieta allowed one run in six innings, and the Cubs' first-inning small ball proved enough against a Nationals team that has lost six of its last seven.

Arrieta (5-4) struck out eight, walked none and gave up six hits. The right-hander earned his first win since May 12.

Nationals left-hander Gio Gonzalez allowed two runs in six innings as Washington lost its third straight and sixth of seven.

Gonzalez (4-3) allowed four hits and four walks, two of each during a first inning when he threw 32 pitches and the Cubs scored on a bases-loaded walk and a run-scoring double play.

"Six innings, two runs, even with all that storm in the first inning, I'll take it any day of the week," Gonzalez said. "It's keeping your team in the game as much as possible."

Hector Rondon worked the ninth for his 10th save, but it was dicey until Ross and first baseman Anthony Rizzo intervened with their pickoff play.

"I absolutely love it," Maddon said of the play. "If he actually had thrown that ball down the right field corner, I would've been fine. I would've been absolutely fine with the whole play because it was the right thing to do. They saw something, they went with it, it was all them. Spectacular."

In the inning, left fielder Michael Taylor hit a one-out single, his third of the game, and then got to second when Rondon walked Robinson.

Center fielder Denard Span flew out to center for the second out. Then with infielder Anthony Rendon at the plate, Ross threw back to first following a 2-1 pitch, easily nabbing Robinson.

"That's just on me, that can't happen," Robinson said. "I really can't explain it. I wasn't really trying to go anywhere. I just couldn't get back fast enough."

The right-handed hitting Ross was making his third consecutive start behind the plate for the first time since early September of 2012, with the Cubs facing their second lefty in that stretch.

The victory moved Chicago to 15-10 in one-run games. In this latest tight contest, Rizzo said he felt comfortable calling the pickoff play.

"I'm always looking for that," Rizzo said. "He's the (go-ahead) run so he's getting a big aggressive secondary lead. Rossy gave me a look and confirmed the signs, and made a good throw."

Right fielder Bryce Harper drove in Washington's run on a sixth-inning, bases-loaded groundout that replays appeared to show he beat out. Washington already had used its challenge on second baseman Danny Espinosa's fourth-inning steal attempt.

After Harper's chopper, Arrieta then hit first baseman Ryan Zimmerman to load the bases again, but shortstop Ian Desmond popped to short to end the inning.

Rendon struck out against reliever Jason Motte to strand runners on first and second in the seventh. He had a single and a double in his return from the disabled list, but infield teammate Yunel Escobar departed after failing to check his swing on a first-inning strikeout.

The Cubs took a 2-0 lead in the first. Right fielder Junior Lake drew a bases-loaded walk, and shortstop Starlin Castro grounded into a run-scoring double play.

Rendon singled in his first at-bat in the bottom of first, but he was caught stealing to end the inning after Escoba