WASHINGTON (AP) -- Not even a visit from the usually cooperative Miami Marlins could bring the Washington Nationals out of their offensive funk.
Adam LaRoche homered in his second game back from the disabled list, but the Nationals managed only three hits and fell 3-2 to the Marlins Monday afternoon.
The Nationals had won 12 of their last 13 against Miami at home, but have now lost five of their last six overall, while scoring three runs or fewer in each loss.
"Right now, it's a question of getting that big hit when we need it," Nationals manager Matt Williams said. "It hasn't happened, for the most part anyway."
Tanner Roark (3-3) went seven innings, allowing three runs or less for his fourth consecutive start. He struck out four and walked one while allowing five hits.
But Giancarlo Stanton's NL-leading 15th home run gave the Marlins enough breathing room to seal their first win at Nationals Park this season.
Roark has taken the loss in his last two starts while allowing five runs -- four earned -- in 13 innings.
"It will turn around," Roark said of Washington's struggles. "We've just got to keep plugging away and not dwell on anything"
Stanton doubled and scored in the first inning, drove two runs in on his third-inning blast to deep center, and later singled in his latest power performance in Washington.
He is hitting .333 (43 for 129) with 14 home runs and 27 RBIs in Washington since his career began in 2010. Stanton has homered at Nationals Park more than any other visiting player during that time.
The Marlins improved to 7-17 on the road; they're 20-8 at home.
Nathan Eovaldi (4-2) pitched 6 1-3 innings, giving up two runs and all three hits. Steve Cishek worked a perfect ninth for his 11th save.
Washington trailed 3-0 and had only one hit before Jayson Werth singled with one out in the sixth. LaRoche homered into the second deck in right to cut the deficit to 3-2.
"Great to come back," said LaRoche, who before Sunday's game had missed just over two weeks with a strained right quad. "Frustrating game today. I feel we just, we didn't give ourselves a ton of opportunities."
Eovaldi left after hitting Nate McLouth with one out in the seventh. Mike Dunn retired pinch-hitter Tyler Moore and Denard Span, reliever A.J. Ramos pitched a perfect eighth.
The Marlins got to Roark for a two-out run in the first when Stanton doubled to right just beyond the reach of Werth and scored on Casey McGehee's single. McGehee is hitting .434 (23 for 53) with runners in scoring position.
Stanton and the Marlins struck again with two outs in the third. After Derek Dietrich was hit by a pitch, Stanton launched the first offering he saw to straightaway center, with the ball bouncing high off a wall beyond the wall.
"I'll tell you this, if it's a hanging breaking ball, he can hit it over the fence, and that's what it was," Williams said of Stanton's home run. "Tanner certainly didn't want to throw it there. . If you hang that breaking ball over the plate, sometimes it gets whacked. And the guy whacked it today."
Miami had a chance for more in the sixth when McGehee doubled with one out, but he was picked off second by Roark.
NOTES: Washington 3B Ryan Zimmerman, on the DL since April 13 with a broken right thumb, had an X-ray on Monday and has been cleared to begin hitting. ... Marlins manager Mike Redmond said 37-year-old Randy Wolf, who allowed six runs (four earned) on eight hits Sunday in his first start since 2012, will remain in the rotation and pitch Saturday against Atlanta. ... Miami's Henderson Alvarez (2-3, 3.21) opposes Blake Treinen (0-2, 1.56) Tuesday.
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