Updated

(SportsNetwork.com) - Gio Gonzalez will attempt to pick up his first victory since early July on Saturday evening when the Washington Nationals play the second contest of a three-game set with the Pittsburgh Pirates.

Gonzalez has lost five consecutive decisions and four straight starts, having not found the win column since July 5. That drought has dropped the left- hander to 6-9 on the year with a 4.00 earned run average.

Gonzalez lasted only 4 2/3 innings on Sunday versus Atlanta, charged with two runs but on six hits and four walks. He also struck out eight as his pitch count ran high early.

"They were fouling off pitches," Gonzalez said. "They kept running up my pitch count. There were a couple of guys at the bottom of the order that were fouling me off for seven or eight pitches, maybe nine."

The 28-year-old is unbeaten in four previous starts versus the Pirates, going 2-0 with a 3.28 ERA.

Jeff Locke counters for the Pirates having won consecutive starts, though he needed a bit of offensive support to beat Detroit on Monday. The southpaw yielded four runs on eight hits and four walks over five innings, but won an 11-6 decision.

Locke is 4-3 with a 3.98 ERA on the year, but has posted a 6.38 ERA over his last four starts.

The 26-year-old will face the Nationals for the second time in his career. He did not get a decision in the first encounter, charged with four runs -- three earned -- on three hits and three walks over five innings.

Pittsburgh will try to snap Washington's win streak at four straight after the Nationals took last night's opener 5-4. Tanner Roark pitched into the sixth inning and the Nats scored some early runs to hold off the Pirates.

Adam LaRoche had a pair of RBI singles and Bryce Harper added a two-run base hit for the NL East-leading Nats. Roark scattered three runs over 5 2/3 frames to win his 12th game.

"We feel great. Confidence is high in this clubhouse," Roark. "With the guys that we have, the veterans that we have, we're just keeping it loose."

Charlie Morton endured a 31-pitch first inning and suffered the loss after allowing seven hits and five runs in three frames.

"It's really just managing the at-bats, each at-bat, and I didn't," Morton said.

Starling Marte hit a two-run homer and Pedro Alvarez had the other two RBI for the Pirates, who lost their third in a row since tying their season-high water mark of nine games over .500. They are now 3 1/2 games out of first place in the NL Central.

Pittsburgh won three of four games versus the Nationals at PNC Park from May 22-25 and has won six of the last nine games in this series.