Zimmerman drives in 4 as Nationals beat Pirates 8-1 behind Marquis

Ryan Zimmerman drove in four runs, Adam Dunn homered and Jason Marquis won his second in a row after previously going winless all season as the Nationals beat the Pirates 8-1 in a matchup of last-place clubs Sunday.

The Nationals outscored the Pirates 17-3 in the final two games of the three-game set for their first road series victory in 18 attempts since they won two of three against the Mets from May 10-12.

Washington did most of its damage against Pirates right-hander Charlie Morton (1-11), who gave up six runs and eight hits over 3 2-3 innings yet still lowered his ERA to 9.66 because four runs were unearned. Morton began the game with a 10.03 ERA that was the third highest in major league history at this stage of a season for a pitcher with at least 10 decisions, according to STATS LLC.

Morton was 1-9 in 10 starts before going to Triple-A Indianapolis for three months. Since rejoining the Pirates, he has given up 14 runs, nine earned, and 17 hits in seven innings during two losses.

Marquis wasn't much better that Morton coming in with a 1-7 record and 8.13 ERA, but limited the Pirates to Pedro Alvarez's solo home run — his 11th — in the fourth while giving up six hits over six innings.

The right-hander had lost 10 consecutive decisions dating to last season before beating Florida 9-3 on Tuesday, but won his fourth in a row against Pittsburgh. Since 2008, he is 6-1 in eight starts facing the Pirates, and his 11 career victories against them are his most against any opponent.

Washington scored an unearned run in the first that resulted from Morton's throwing error on a pickoff attempt, then gave Marquis all the support he needed with a five-run fourth inning. Dunn started it with his 34th homer, an opposite-field drive to left. First baseman Garrett Jones' error for misplaying Adam Kennedy led to Ian Desmond's RBI single and Zimmerman's two-run single.

Zimmerman and Dunn singled in runs in the sixth against right-hander Joe Martinez, who pitched three innings after being called up from Triple-A Indianapolis. He was acquired in a July 31 trade with San Francisco.

Washington's bullpen followed Marquis with three scoreless innings, two by Tyler Clippard and one by Drew Storen.

Notes: The Pirates unveiled a statue of Hall of Fame second baseman Bill Mazeroski in pregame ceremonies. ... Nationals manager Jim Riggleman returned after serving a two-game suspension for his role in last week's brawl against Florida. Nationals 3B coach Pat Listach began serving his two-game suspension and was replaced by Rick Eckstein. ... Washington won five of six in a season series noteworthy for Stephen Strasburg's 14-strikeout debut during the Nationals' 5-2 victory on June 8. ... The Pirates' 91st loss, with 26 games remaining, was their seventh in nine games. ... Pittsburgh would trail Washington by 13½ games if the two were in the same division. ... Pittsburgh committed three errors.