The Marlins, bidding for their first playoff berth since 2003, are in second place in the NL East but have lost three of their past four games, all at home against last-place teams.
That includes the Nationals, staggering to the end of a disappointing season after winning the World Series in 2019. They're the spoilers in the five-game weekend series.
"I guess so," Gomes said. "If you want to call it that, we'll take it and make everybody work for it."
The Nationals were swinging early in the count against Sanchez (3-2). He had given up a total of six runs in his first five career starts, but allowed eight hits and five runs in four innings, and his ERA rose from 1.69 to 2.75.
Washington was the first opponent to face Sanchez for a second time.
"You don't want to get deep in counts against that guy," Gomes said. "He's a tremendous young guy. We were just trying to get something early in the count and do the damage we can."
Andrew Stevenson, recalled before the game from the Nationals' alternate training site, had a two-run single for his first hit this year.
Fedde (2-3) walked two, hit a batter and matched a career high in innings, lowering his ERA from 5.06 to 4.36.
"I was able to be really effective inside, and it opened up the down and away," Fedde said. "It's nice when you can hit your spots consistently and get the calls. A good day."
Will Harris pitched the seventh to complete the two-hitter.
Washington scored twice in the second on four consecutive hits, including an RBI double by Garcia and a run-scoring single by Carter Kieboom.
Five consecutive Nationals reached in the fourth. Stevenson hit a two-run single, and Victor Robles' RBI single made it 5-0.
Nationals: RF Adam Eaton, batting a career-low .226, went on the injured list with a broken left index finger. "It's fitting for how my year has gone to end on that note," he said. "It has been a trying year, to say the least." The Nationals hold a team option on Eaton for 2021, so he may have played his last game for them. "I don't want to look too far ahead, because I'll drive myself crazy," Eaton said. "But this organization has been nothing but good to me."
Nationals: INF/OF Brock Holt was reinstated from the paternity list. OF Yadiel Hernandez was optioned to the alternate training site, and RHP Wil Crowe was designated the 29th man for the doubleheader.
Marlins: RHP Johan Quezada was optioned to Miami's alternate training site. RHP Robert Dugger was recalled, and LHP Dan Castano was appointed the 29th man for the doubleheader.
Nationals: RHP Wil Crowe (0-1, 7.50 ERA) gets the ball for the second game of the doubleheader. LHP Patrick Corbin (2-5, 4.10 ERA) is scheduled to start Saturday in the third game of the series.
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