CHICAGO -- Tyler Moore went 2-for-3 and drove in the go-ahead run in the sixth inning and his Washington teammates added two insurance runs in the ninth in the Nationals' 4-2 victory over the Chicago Cubs on Tuesday night at Wrigley Field.
Nationals starter Dan Haren (8-11) scattered five hits in six innings for his fourth win in his last five starts. Rafael Soriano worked the ninth for his 32nd save.
The victory stopped a two-game Nationals skid and was the 300th over the Cubs in franchise history, including 35 seasons as the Montreal Expos. The Expos/Nationals have also won 300-plus games against the Mets (375) and Phillies (356).
Moore drove in Ryan Zimmerman from third base with two outs in the sixth to give the Nationals a 2-1 lead. Cubs starter Chris Rusin was pulled after the next batter -- Anthony Rendon -- singled to put runners at first and second.
Chicago reliever Blake Parker walked pinch-hitter Adam LaRoche to load the bases for Haren, who ended the inning grounding out to short.
Rusin (2-3) worked 5 2/3 innings and gave up two earned runs and 10 hits, walked two and struck out two.
Haren pitched six full innings and gave up one earned run and five hits. He struck out six and walked none.
The Nationals added a run in the ninth when Bryce Harper led off with a double to right against Cubs left-hander James Russell and scored on Ian Desmond's single to right against Kevin Gregg, the fifth Chicago pitcher.
Gregg then walked Zimmerman and Jayson Werth before Denard Span delivered a two-out RBI single to score Zimmerman for a 4-1 edge.
Donnie Murphy's leadoff homer for the Cubs in the ninth off Soriano trimmed the Washington lead to 4-2.
Zimmerman, Rendon, Harper Desmond and Wilson Ramos also had two hits for Washington.
Washington jumped to a 1-0 lead in the first inning. Harper singled, then was forced out on Desmond's grounder. Desmond scored from first on Zimmerman's double.
Chicago's Brian Bogusevic tied the score with his first home run of the season in the fourth. He launched a high, deep fly to center on a 2-2 pitch by Haren for his first home run since Sept. 29, 2012, at Milwaukee.
NOTES: Chicago 1B Anthony Rizzo was back in the starting lineup after missing Monday's game with an unspecified illness. ... Washington sends RHP Ross Ohlendorf (2-0, 1.85 ERA) against Cubs RHP Jake Arrieta (1-0, 0.69) in Wednesday's third game of the four-game series. ... Nationals LHP Ian Krol is making his first trip to Chicago as a major-leaguer. He was born and raised in the area and was also a top pitcher for the suburban Class A Kane County Cougars, where he was pitcher of the year in 2010 while in the Oakland A's organization. ... In his past 21 games before Tuesday, Cubs C Welington Castillo had a .328 average with three doubles, two home runs and six RBIs.