WASHINGTON -- Amed Rosario had two hits, including a solo homer in the eighth inning to break a tie, as the New York Mets defeated the Washington Nationals 6-5 on Sunday after blowing a 5-0 lead in the first game of a day-night doubleheader.

It was the fourth homer of the year and career for Rosario, a rookie who hit a 0-2 pitch from Joe Blanton (2-3) over the fence in center to make it 6-5.

That made a winner of Mets reliever Jerry Blevins (6-0), who retired two batters without giving up a hit or run against his former team.

Mets closer A.J. Ramos got the last three outs in the eighth, as the Nationals left the bases loaded. Ramos also pitched the ninth for his fifth save with the Mets and 25th overall.

The game ended as pinch-runner Edwin Jackson was thrown out at the plate after a double to center by Daniel Murphy. Jackson was running for Adam Lind, who singled with two outs before the hit by Murphy.

The call was upheld after a challenge by the Nats.

The Mets took a 3-0 lead in the first as Asdrubal Cabrera hit a three-run homer off Washington rookie Erick Fedde. It was the 10th homer of the season for Cabrera, who played for the Nationals for part of the 2014 season.

Wilmer Flores hit his career-high 17th homer in the third, a two-run shot that gave the Mets a 5-0 advantage. Flores, who was 4-for-4, hit 16 homers in both 2015 and 2016.

But the first-place Nationals (77-51) began their comeback as Wilmer Difo had an RBI single in the fifth to make it 5-1. Washington's Alejandro de Aza (2-for-3) drove in a run with a double and Howie Kendrick (3-for-4) had a sacrifice fly later in the sixth to trim the margin to 5-3.

The Nationals tied the score at 5 with two runs in the seventh when Michael A. Taylor had an RBI double and de Aza had a sacrifice fly.

It was the third major league start for Fedde, the top pitching prospect for the Nationals. He was filling in for ace Max Scherzer (neck), who had his start moved back to Monday.

Fedde threw 112 pitches. The most he threw in any start in the minors this year was 108 for Triple-A Syracuse on Aug. 13 at Indianapolis.

Mets starter Tom Milone, a former Nationals prospect, gave up six hits and one run with one walk and five strikeouts in 4 1/3 innings.

Juan Lagares and Matt Reynolds had two hits each for the Mets (57-72).

Rafael Bautista and Matt Wieters also had two hits for Washington.

NOTES: Washington RHP Erick Fedde was added as the 26th man for the doubleheader in order to start the first game. Nationals RHP A.J. Cole was sent to Triple-A Syracuse and OF Rafael Bautista was called back from Syracuse. ... The Mets activated RHP Seth Lugo from the disabled list and sent RHP Robert Gsellman to Triple-A Las Vegas. RHP Kevin McGowan was added as the 26th man for the doubleheader. ... Washington RHP Max Scherzer (12-5, 2.25 ERA) is slated to face Marlins RHP Jose Urena (12-5, 3.68) on Monday at Nationals Park. ... Mets rookie RHP Chris Flexen (3-2, 5.79) will start Tuesday in Cincinnati against Reds RHP Sal Romano (3-5, 4.96).