MIAMI -- Six days after facing Justin Nicolino in Washington, the Nationals had a pretty good idea of what to expect on Friday night. So they came out swinging, and behind second-inning home runs from Ryan Zimmerman and Michael Taylor, the Nationals broke out to a four-run lead and never looked back in a 4-1 win over Miami at Marlins Park.
"I think he was missing over the plate. I think we just took advantage of it, put a four spot on him," Jayson Werth said. "That was the difference in the game. He's got good stuff."
• Aggressive approach creates four-run second
Staked to an early lead, Tanner Roark gave up one run and struck out seven in 6 2/3 innings, as the Nationals took the first game of the series and moved 4 1/2 games ahead of Miami, which has dropped three straight for the first time since losing four in a row from April 13-17.

"We haven't really been able to break through lately, but that's also part of the game," Marlins manager Don Mattingly said. "I think we've shot ourselves in the foot, baserunning-wise, lately. We've had a number of plays."
Marcell Ozuna connected on his eighth home run, a solo shot off Roark in the fourth inning, but that was all Miami could manufacture. Giancarlo Stanton was hitless in four at-bats, with three strikeouts. He is now hitless in his last 16 at-bats.
"I'm not a guy who walks people. They know that, too," Nicolino said. "I think that's why they came out swinging, because they knew I was going to make an adjustment and attack the zone. They did their part in the second inning. But the biggest thing was not walking guys and pounding the zone and using all pitches to get those guys out, and it happened."
MOMENTS THAT MATTERED
Bouncing back: The Nationals searched all week for an answer to why Roark had struggled so mightily against the Marlins this season, against whom he was 0-3 with an 8.40 ERA. But Roark put to rest those questions with a strong outing. He scattered six hits and struck out seven in 6 2/3 innings. The only run he allowed was a solo homer by Ozuna in the fourth.
"I mixed it up a little bit, the game within the game," Roark said. "It was a little minor adjustment that I did, and it worked." More >

Stanton's slump continues: After going hitless in 10 at-bats with nine strikeouts in the three games at Philadelphia, Stanton took early batting practice on the field with hitting coach Barry Bonds, with manager Don Mattingly watching. The slugger came close to connecting in his fourth at-bat off Shawn Kelley. In a rare at-bat without wearing his face guard against a right-handed pitcher, Stanton ended up striking out with a runner on first and the count full. Still, he nearly came up big, lifting a long foul ball to right field. It had the distance to be gone, but it drifted foul. Since May 3, Stanton is batting .158 (9-for-57) with 25 strikeouts and three home runs. More >

Escape act: Roark exited in the seventh after a two-out walk. Left-hander Felipe Rivero entered the game and promptly allowed a single to Derek Dietrich to bring the tying run to the plate in Martin Prado. But Rivero worked his way out of the jam, forcing Prado to ground out back to the mound to end the inning. It was an encouraging sign for Rivero, who entered the game with a 4.58 ERA.

Nicolino stunned, then settles: From the first pitch, when Taylor lined out to left, the Nationals were hitting the ball hard off Nicolino. The Marlins' lefty was rocked in the second inning, giving up four runs, including homers to Zimmerman and Taylor. Nicolino had allowed just one home run over his first 25 innings this season before surrendering two in the same frame. From there, the lefty retired the next 10 before Bryce Harper's double led off the sixth. Nicolino was lifted after 63 pitches. He received help from shortstop Adeiny Hechavarria on Daniel Murphy's grounder, as he threw Harper out trying to advance to third in that frame.
"They were just ambushing my pitches in," Nicolino said. "I think that was their approach -- hit those fastballs in. They knew they were going to get it, because I was going to pound in. Later on in the outing, I started establishing away, and it showed because they were looking for heaters and cutters in. That four-run inning put us in a hole, but [we] bounced back. That's what we needed, a little momentum."

QUOTABLE
"That's just a mistake we talk about. We're down to eight outs at that point before that out. You're down three runs. I think it's not playing the scoreboard. That's one of the things we talk about. We continue to talk about. You have to play the scoreboard there. That's really got to be 100 percent. It's one of those that can't be close. It's something we'll talk about." -- Mattingly, on Hechavarria trying to stretch a single to a double and being thrown out in the seventh inning with Miami trailing by three
"Hopefully we'll have a few more years to get the numbers up a little bit." -- Werth, on his .224 average on his birthday
SOUND SMART WITH YOUR FRIENDS
Werth celebrated his 37th birthday and went 2-for-4 with his first outfield assist of the season. Since joining the Nationals in 2011, he is 6-for-13 with two homers and five RBIs on his birthday.
UPON FURTHER REVIEW
Harper began the sixth inning with a leadoff double, but he ran into a forceout at third base when the next batter, Murphy, hit a grounder to shortstop Hechavarria. The Nationals challenged, but the call on the field was upheld.

The Marlins made their challenge in the seventh, questioning the out call on Hechavarria, who was attempting to stretch a single into a double with one out. After a review of two minutes and eight seconds, the call was confirmed.

The third review was a complex, three-minute, 52-second one, involving a potential double play in the ninth inning. On Wilson Ramos' grounder to Hechavarria, the Marlins tried to turn two, but after getting the force at second, Dietrich's throw to first caused Justin Bour to come off the bag, so Ramos was ruled safe. The entire play was reviewed, with looks at first, second base and the slide rule. The out at second was confirmed, but the call stood on the questionable play at first.

WHAT'S NEXT
Nationals:Joe Ross, who turns 23 on Saturday, will take the mound for the Nationals at 7:15 p.m. ET in his second consecutive start against the Marlins. He was tagged for five runs (three earned) in 5 2/3 innings against Miami last Sunday at Nationals Park. He carries a 2.63 ERA into this game.
Marlins:Jose Fernandez, coming off being the National League Player of the Week, will take the mound. The right-hander is 5-2 (3.21 ERA) on the season, and he is 20-1 (1.65 ERA) in his career at home.
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