(SportsNetwork.com) - The Washington Nationals are moving closer to an NL East title and shoot for a three-game sweep of the Atlanta Braves Wednesday afternoon in DC.

The Nationals have won three in a row, including the first two portions of this series, and pushed their lead atop the division standings to nine games ahead of the Braves with Tuesday's 6-4 victory.

Washington scored four runs in the first inning and made it 5-0 by the second en route to the win. Adam LaRoche had two hits and two RBI, Wilson Ramos went 2-for-4 and drove in a run and starting pitcher Jordan Zimmermann tossed six solid innings for the win. Zimmermann improved to 11-5 this season and was reached for four runs, two of which were earned, and struck out seven.

"We're still taking it one game at a time," Zimmermann said. "We're not looking too far ahead."

Nationals shortstop Ian Desmond left Tuesday's game in the sixth inning because of lower back tightness and is day-to-day. Desmond is batting .248 with 22 home runs and 83 RBI.

"I feel like I can play tomorrow. This is something I've had before," Desmond told the club's website. "I'll sleep tonight, get some treatment and I should be all right tomorrow. This isn't something I have to deal with every day. It's something that pops up. I probably had it two or three times this year, where it just comes and goes. So it's no big deal."

The Nats' magic number to clinch an NL East title for the second time in three years is down to 10. They are 3-2 on a six-game homestand and will begin an 11-game road trip Thursday with the first of four games against the New York Mets.

The Nationals have won each of Stephen Strasburg's last four starts and will send the right-hander to the mound Wednesday. Strasburg is 3-0 over the aforementioned winning streak and 4-1 in his previous five decisions. In his last outing on Aug. 30, Strasburg struck out eight batters and allowed only a run in 7 2/3 innings of a 3-1 victory.

Strasburg is 11-10 with a 3.43 ERA this season and 8-2 in 16 home starts. He has made 15 career starts against the Braves, going just 3-6 with a 4.62 ERA. Atlanta hammered Strasburg for seven runs over five innings of a 7-6 decision on Aug. 8 at Turner Field.

The Braves have dropped three in a row and six of their last eight games, and fell to 1-4 on a nine-game road trip.

Ervin Santana struggled in the start for Atlanta on Tuesday, as he gave up six runs (5 earned) and eight hits in five innings.

"They came out swinging the bats and were really, really aggressive with the first couple pitches of every at-bat," manager Fredi Gonzalez said. "Usually, when teams do that against (Santana), they get quick outs. But they found the outfield grass and put a big number up. We weren't able to recover after that, but we battled."

Justin Upton hit a two-run homer and both Jason Heyward and Chris Johnson added an RBI for the Braves, who are even with Milwaukee at 1 1/2 games off the final wild card berth in the National League.

The Braves will close out the road trip this weekend in Texas.

Aaron Harang toes the rubber for the Braves this afternoon and he is 10-10 with a 3.87 earned run average. Harang has lost three straight starts and fell to 1-4 in his past five decisions with last Friday's 11-3 loss at Miami, where he allowed six runs and 10 hits in only 3 2/3 innings.

Harang has allowed three or more runs in five straight appearances and has pitched to a 6-5 mark in 14 road starts this season. The veteran right-hander, though, has struggled in 11 career starts against the Nationals as evidenced by his 2-4 record and 3.45 ERA.

He tossed seven innings of one-run ball in a 4-1 loss to the Nationals on Aug. 9 at Turner Field, and did not receive a decision.

Atlanta is 9-6 against Washington this season.