The Washington Nationals are putting together a power surge that they hope can carry them deep into October.

Starter Jordan Zimmermann could be happy to see more offense on Thursday night as he attempts to snap a personal four-start winless stretch and hurl the Nationals franchise to its first four-game sweep of the Chicago Cubs in over 15 years.

Washington has put on an offensive showcase over the first seven contests of an 11-game homestand. The Nats are 6-1 so far on the stay while hitting .349 with 19 homers.

Twelve of those have come in the past two games, with Washington following up a six-homer victory on Tuesday with another six longballs in Wednesday's 9-1 victory.

Bryce Harper had a pair of homers and Adam LaRoche added a two-run shot. Roger Bernadina, Ian Desmond and Danny Espinosa all added home runs in Washington's fourth straight victory as it continues to lead the Atlanta Braves by 7 1/2 games for first place in the NL East.

"After about the third or fourth one tonight, we were saying 'what is going on around here?' It's great timing for us to keep pushing hard," LaRoche said.

LaRoche and Harper have been at the front of the surge. LaRoche has homered five times and driven in nine runs over five games this month while going 10- for-18 at the plate, while the rookie Harper is batting .382 with five home runs and 10 RBI over his last nine games.

Lost in the offensive display was Gio Gonzalez earning his MLB high-tying 18th win of the season. He took a no-hitter into the sixth inning and ended up yielding three hits while striking out nine without a walk over seven scoreless frames.

"I see his highlights every fifth day, it's just Gio being Gio," said Cubs rookie Anthony Rizzo, who homered in the ninth inning to prevent the shutout. "They have something good over there."

Chris Volstad took the loss after allowing five runs on nine hits and four walks over five innings for the Cubs, who have dropped five in a row and will try to avoid getting swept in four games in this series since the Montreal Expos turned the trick at home on June 6-9, 1997.

Zimmermann hopes another offensive surge isn't necessary tonight, but he'll need to shake off some recent issues if that is to be the case.

The right-hander is 0-2 with a 7.91 earned run average in his last four outings and is coming off a horrid performance on Saturday versus the St. Louis Cardinals.

Zimmermann lasted a season-low 3 2/3 innings and was touched for a career-high eight runs on eight hits, though he did not get a decision in his club's 10-9 loss. He is 9-8 through 27 starts and his ERA has gone from 2.35 to 3.01 over his winless stretch.

The 26-year-old is 0-3 with a 4.68 ERA in four lifetime meetings with the Cubs. He held them to a pair of runs -- one earned -- on six hits over seven frames on April 8, but took a 4-3 loss.

Chicago's Justin Germano tries to avoid a fourth straight losing start in this finale and has been drilled for 17 runs over 14 2/3 innings of his current losing streak for a 10.43 ERA.

The 30-year-old righty lasted five innings on Saturday against the San Francisco Giants, charged with five runs on six hits and two walks to fall to 2-5 with a 6.30 ERA in eight appearances with the Cubs this season.

Germano has faced the Nationals just once before, on June 2, 2007 while with the San Diego Padres. He picked up a win, allowing three runs over six innings.

The Nationals have won five of six versus the Cubs this season.