Washington did it behind another strong showing from a starting pitcher. Over the last six games, Nationals starters have allowed just four earned runs in 39 1/3 innings.
"That's kind of the way it's been all year," said Drew Storen, who recorded his seventh save of the month. "You look at what the starting staff has done. Those guys come out and they attack guys. You see the way they work ahead in the count, so we're just kind of piggy-backing what they're doing."
Fister, who watched the Nats score 10 runs in his previous outing last Saturday, yielded two runs and scattered five hits over 6 2/3 innings, and he was rewarded with his team-leading 15th win of the season.
Despite garnering some praise from his manager and the opposing clubhouse, Fister wasn't convinced he'd pitched at his best on Friday.
"I definitely wasn't as sharp as I should've been. There were some hard-hit balls that our guys made some great plays on," he said. "It's something that I have to build on. I can't let one rough outing get to me, but I also need to be able to build."
All Miami's damage came off the bat of rookie Justin Bour, who drove in the club's first run on a groundout in the second inning. In his next at-bat, Bour cranked his first big league homer to lead off the fourth.
But those were the only real mistakes by Fister, who retired 10 of the next 12 batters following the home run. Manager Matt Williams removed him with two outs in the seventh inning in favor of southpaw Matt Thornton, with lefty pinch-hitter Jordany Valdespin on deck. Thornton, who hadn't pitched since Sunday, walked Valdespin, but got the left-handed-hitting Christian Yelich to ground out.
"Given where we're at and given the fact that he hadn't been in the game in five days, we had to get him in there," Williams said. "That's the spot for him."
For all his wildness, the Nats couldn't crack Marlins starter Tom Koehler for more than three runs in his five innings. They went 1-for-6 with runners in scoring position and left six men on base against him.
The Nationals did, however, continue their two-out hitting from Thursday, when they scored four runs with two outs. All three Washington runs Friday also came with two outs. The first two came on one swing by Adam LaRoche, who, in his first at-bat since taking two games off to deal with back soreness, drilled the eighth pitch into the upper deck in right field. The home run scored Jayson Werth, who drew a two-out walk.
Denard Span, who recorded his 56th multihit game of the year, drove in the third run on a liner to right in the fourth inning. He also recorded his eighth triple of the year to lead off the third, but he was stranded when LaRoche struck out and Ian Desmond lined into a double play with the bases loaded.
"They're a good lineup, and Fister has been pitching real good," Koehler said. "Any time you kind of give them a two-point advantage before we even get started, it's going to be tough. There is a reason they are where they are. They got that two-run lead, and they were able to keep it."
The Nationals couldn't get anything else going against the Marlins, save for a Werth single in the seventh. But the Marlins didn't put up much of a threat either, as Tyler Clippard worked a five-pitch eighth and Storen needed just six pitches to get through a perfect ninth.
"We stuck together and played as a team, and it works for us," Fister said. "We grind out the one-run ballgames and make them work."