WASHINGTON -- Jordan Zimmermann is not a .500 pitcher, and after a sluggish start, he is finally starting to put together the efforts that elevated him into the National League's elite.

Zimmermann posted his third consecutive strong outing, and the Washington Nationals got a sixth-inning home run from catcher Wilson Ramos in a 3-1 victory over the Giants on Sunday night, sending San Francisco home after an 0-6 road trip it would like to forget.

After taking his third straight defeat on June 17, Zimmermann had a pedestrian 5-5 record. Since then, he has pitched 22 2/3 innings of impressive ball, allowing one run and 15 hits while striking out 17 batters, including a season-high-tying eight against the Giants.

He wound up permitting one run on three hits and one walk in seven innings.

"I had to settle down and start making some pitches, and I was able to do that," Zimmermann said of his work after he allowed two first-inning singles. "I was battling for the most part, and I was able to get some big outs when I needed to. The curveball has been probably my best pitch over my last four starts."

Zimmermann (7-5) had the Giants fooled early, as he recorded five caught-looking strikeouts through the first five innings, although San Francisco did not agree with all of them. Center fielder Angel Pagan was particularly vocal after being called out on a high fastball in the third, and he was fortunate not to get thrown out by plate umpire Phil Cuzzi.

"There's frustration, as there should have been," said Giants manager Bruce Bochy, who was tossed along with San Francisco right-hander Ryan Vogelsong in the fifth inning. "There were some calls, and I know our guys were frustrated."

Zimmermann made just one mistake, grooving a 3-0 pitch to San Francisco shortstop Brandon Crawford, who connected for his 12th homer of the season in the fourth inning to tie the game 1-1. Aside from that, the Nationals starter was on point.

"He was amazing," Ramos said. "He threw the ball pretty good. He was attacking the hitters pretty well. In the last three starts, he's been amazing. He's throwing really good, all the pitches are good. I'm happy for him and for me, too, because we stay on the same page. When we stay on the same page, we have a game like tonight."

The Giants lost their seventh consecutive road game, and they have just three wins in their past 12 games away from San Francisco.

"Zimmermann is good," Bochy said. "We had a tough time against this staff -- we got five runs in the series, and that usually doesn't work. We ran into some great pitching on this road trip. It's a tough trip -- there's no getting around that."

San Francisco also fell for the 12th time in its past 14 games at Nationals Park. Bochy and Vogelsong were not around for most of the contest, both tossed for arguing balls and strikes. The right-hander was ejected for the first time in his career.

"I'm not going to get into what the exchange was," Vogelsong said. "Obviously, I was frustrated with the pitch, and I guess he was frustrated with my reaction, and I got thrown out. There was an exchange, but it's not worth getting into. I pitch with a lot of emotion all the time, so tonight just boiled over and got the best of me."

Ramos broke the 1-1 tie in the sixth with his eighth homer of the season, a shot to right-center off reliever George Kontos (2-1). The catcher also drove in an insurance run with an eighth-inning single.

"When I hit the ball, I thought it was gone, but I saw the replay and saw it was just behind the wall," Ramos said of his homer. "Next time, I need to hit it harder and run a little bit harder."

Drew Storen pitched the ninth for his 25th save of the season for the Nationals, who are 12-3 over their past 15 games to move to 10 games over .500 for the first time this season.

NOTES: The Nationals placed RHP Stephen Strasburg on the disabled list due to a left oblique strain. "He's disappointed about it and so are we," manager Matt Williams said. The team recalled RHP Taylor Jordan to take his spot on the roster. ... Giants OF Hunter Pence took batting practice Sunday, the next step in his recovery from a left forearm injury that has sidelined him since June 2. He hit several balls over the fence during his time in the cage. ... Nationals OF Bryce Harper and Giants C Buster Posey were announced as All-Star starters before Sunday's games. Harper led all NL vote-getters, while Posey was a landslide selection at catcher. ... Former Giants 1B Travis Ishikawa, who was designated for assignment by the team Tuesday, was claimed off waivers by the Pittsburgh Pirates.