WASHINGTON -- The Miami Marlins decided to go to their bullpen after a rain delay of 1 hour, 25 minutes in the middle of the second inning Thursday, while the Washington Nationals stayed with starter Tanner Roark.
The visitors' decision paid off.
Marlins reliever David Phelps pitched four scoreless innings for the win, and a bevy of two-out hits were the difference as Miami earned a 6-4 victory in Washington's home opener.
"We didn't get any two-out hits," Dusty Baker said after his first home game as the Washington skipper. "The difference in the ballgame was they got two-out hits."
Martin Prado and Adeiny Hechavarria each had two hits and drove in two runs for Miami.
"We got a lot of big hits," Marlins manager Don Mattingly said. "The guys swung the bats all day long. We got out of the gate today."
Since 2013, the Marlins were 20-37 against Washington, but they prevailed due to a balanced attack and effective relief pitching.
Phelps (1-0) helped save the Marlins bullpen by throwing 59 pitches -- 36 for strikes. He allowed two hits and two walks while striking out three.
"It was huge," Mattingly said of Phelps. "He is throwing the ball so well."
Miami starter Adam Conley allowed three runs in the first inning.
Regarding possibly leaving Conley in after the delay, Mattingly said, "We gave it all kind of thought. We knew our bullpen would get taxed today. All of those guys stepped up."
A.J. Ramos threw a hitless ninth inning for the save, closing the first win of the season for the Marlins (1-2). The Nationals fell to 2-1.
Roark (0-1) gave up nine hits and four runs (three earned) in four innings. A reliever most of last season and a starter in 2014, he walked three and struck out three.
"I felt great. I stayed loose in the batting cages (during the delay)," said Roark, who pitched two innings before the rain came and two after the delay. "I was just trying to throw every 10 or 15 minutes of about 20 throws to keep my arm loose."
Each team scored three times in the first inning. Miami went in front for good on Hechavarria's third-inning single, and Phelps added an RBI hit in the fifth for a 5-3 lead.
The Marlins tagged on an insurance run in the seventh to make it 6-3. Hechavvaria had an RBI double with two outs to score Justin Bour, a product of nearby George Mason University, who had doubled.
Washington's Bryce Harper hit a solo homer to right in the bottom of the seventh off Bryan Morris to cut the margin to 6-4. Harper also homered on Opening Day in Atlanta on Monday. Harper flied out to deep center to begin the ninth off Ramos.
Bour, Giancarlo Stanton and J.T. Realmuto also had two hits for the Marlins, who gave up 15 runs in their first two losses to the Detroit Tigers.
Daniel Murphy had two hits for the Nationals, including a three-run triple in the first inning, and Anthony Rendon added two hits.
Phelps collected his first major league RBI. He began his career with the New York Yankees in 2012.
The pitcher had a conversation with Mattingly during the rain delay.
"He asked me what my comfort level on my pitch count was," Phelps said. "I told him I can probably give you around 60, and I'll try to stretch it out as much as possible. He was honest with me. He's like, 'We've got to get some length because our bullpen was kind of tired coming in today and we've had two long games before this one.'"
NOTES: The Nationals lost a challenge in the bottom of the fifth when RF Jayson Werth was called out at first via a tag by Justin Bour. If Werth had been ruled safe, the bases would have been loaded with two outs. ... Washington RHP Joe Ross will face Marlins RHP Tom Koehler in the second game of the series Saturday. ... Thursday was the first home game with the Nationals for manager Dusty Baker, who last managed during the 2013 season with the Cincinnati Reds. Baker took over for Matt Williams, who was let go after two seasons. ... Nationals RF Bryce Harper, the reigning National League MVP, has 99 career homers and 98 career doubles. The only other Nationals to reach 100 career homers are 1B Ryan Zimmerman (200) and OF/SS Ian Desmond (110), now with the Texas Rangers. ... Marlins 2B Dee Gordon entered the game with six hits in first 11 at-bats this season and a 12-game hitting streak at Nationals Park. However, he went 0-for-4.