SAN FRANCISCO -- Tanner Roark and three relievers combined on an eight-hit shutout, Ryan Zimmerman homered and scored twice, and the Washington Nationals beat the San Francisco Giants, 3-0, on Monday in a game that featured a benches-clearing brawl in the eighth inning.
Daniel Murphy added two hits and two RBIs and Anthony Rendon singled twice to pace the Nationals in the opener of this three-game series at AT&T Park.
"That's what you do, you win the game first," Nationals manager Dusty Baker said. "That's what we're here for. We're not here to brawl. We're here to win the game. But we're not here to take any stuff, either. Like I said, most teams I've had we don't start anything, but we don't take nothing."

Roark (5-2) pitched seven crisp innings, allowing six hits, walked one and struck out six to win his second straight decision. The right-hander only allowed two runners past first base and got help from catcher Matt Wieters, who threw out a pair of baserunners.
Giants starter Matt Moore (2-6) took the loss despite allowing only two runs over seven innings. The left-hander gave up six hits, struck out five and didn't walk a batter but got no run support.
"I know they're a good lineup, and as a team they've done some good things but I always feel good pitching here," Moore said. "The way we've playing overall in the last two weeks, I think everybody had good feelings going into it."
The game was halted briefly in the top of the eighth after Washington slugger Bryce Harper was hit by a pitch from San Francisco reliever Hunter Strickland. Harper took a few strides toward the mound and flung his batting helmet aside before the two started trading punches.

Both dugouts emptied and there was a lot of pushing and shoving by both teams before order was restored. Strickland, who had to be forcefully removed from the field by a trio of teammates, was ejected along with Harper.
"I don't want to go on a baseball field and try to fight somebody," said Harper, who hit two homers off Strickland in the 2014 National League Division Series. "Especially when it's somebody that it's in the past. It's so in the past that it's not even relevant anymore. They won the World Series that year. I don't even think he should be thinking about what happened in the first round. He should be thinking about wearing that ring home every single night. I don't know why he did it or what he did it for, but I guess it happens."
MOMENTS THAT MATTERED
Another gem by Roark: Roark had cruised along for most of his outing thanks to a strong two-seamer and movement of all of his pitches. In the sixth, the Giants managed perhaps their best scoring threat against Roark after back-to-back two-out singles from Brandon Belt and Buster Posey.
That brought Brandon Crawford to the plate representing the potential go-ahead run, but a curveball from Roark forced him to hit a grounder to Murphy and end the threat.
"We just couldn't do much with their starter," Giants manager Bruce Bochy said. "It's a tough one to lose when you get a quality start like we did from Moore."
Zimmerman's 14th: Zimmerman's home run leading off the second inning was his 14th of the season, second on the Nationals to Harper's 15. More importantly, it was Zimmerman's first long ball in more than three weeks. Washington's first baseman, who entered the day second in batting in the National League, finished with three hits to raise his average to .374.
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QUOTABLE
"After it happened I kind of saw Harper point and the next thing you know he's going out after him. There's some big guys tumbling around on the ground. You see Mike Morse, he's about as big as they come, and he was getting knocked around like a pinball. It's a little dangerous to get in there sometimes." -- Giants catcher Buster Posey
"What's a man supposed to do? He's not a punching bag." -- Baker
"I mean, a baseball's a weapon, and being able to use that to his advantage, that's just what he wanted to do in that situation. You never want to get suspended or anything like that, but sometimes you just have to go and get him. You can't hesitate. You either go to first base or go after him. I decided to go after him." -- Harper
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Roark improved to 6-0 in six career starts against the Giants.
WHAT'S NEXT
Nationals: Left-hander Giovany Gonzalez (3-1, 2.90 ERA) will take the mound as the Nats continue this three-game series Tuesday night at 10:15 p.m. ET at AT&T Park. Gonzalez has cooled off since his hot start in April as he has posted a 4.40 ERA through five starts in May.
Giants:Jeff Samardzija (1-6, 4.50) seeks his first career win against the Nationals in the middle game of this series Tuesday night (7:15 PT) at AT&T Park. Samardzija has at least eight strikeouts in each of his past five starts but is coming off a rough outing against the Cubs when he was tagged for three home runs.
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