NEW YORK -- Yoenis Cespedes launched a grand slam during a nine-run outburst in the eighth inning that rallied the New York Mets past the Washington Nationals 11-5 on Wednesday night, preventing a three-game sweep.
Todd Frazier tied it at 4 with a two-run single and pinch-hitter Juan Lagares put New York ahead for the first time with a two-run double off ineffective setup man Ryan Madson (0-2).
Shut down by Tanner Roark for seven innings, the first-place Mets broke loose in the eighth and improved to 13-4 with a stirring victory against their NL East rivals.
Ryan Zimmerman homered twice, tripled and drove in four runs for the Nationals, who pulled off their own big comeback in the eighth inning of the series opener.
Two nights later, New York returned the favor.
Roark limited the Mets to two hits and left leading 4-2. Michael Conforto, Cespedes and Asdrubal Cabrera singled off Madson to load the bases with nobody out in the eighth. Jay Bruce fouled out before Frazier smacked a two-run single up the middle and advanced to second on the throw home.
After an intentional walk to Adrian Gonzalez loaded the bases again, pinch-hitter Wilmer Flores struck out. Lagares then lined a two-run double the other way, just inside the right-field line at the outer edge of the infield grass, to put the Mets up 6-4.
Sammy Solis walked Amed Rosario and Conforto to force in a run. Cespedes connected for his sixth career slam -- the third by the Mets already this season -- off A.J. Cole, sending fans into a frenzy.
Both of Cespedes' hits in the inning came on 0-2 pitches.
AJ Ramos (1-1) worked a perfect inning for his first win with the Mets since being acquired from Miami last July.
Howie Kendrick reached on an infield single for Washington in the first and Bryce Harper drew his 24th walk, most in the majors. Zimmerman, batting .121 at that point and struggling to make opponents pay for bypassing Harper, came through with a drive to left-center off Steven Matz for his second home run of the season.
Matz steadied himself after a 33-pitch first inning and retired his final 10 batters. He was pulled for a pinch hitter in the fourth after throwing 74 pitches.
Cabrera doubled to open the fourth and scored on Gonzalez's single. Zimmerman had a chance to start an inning-ending double play, but his throwing error from first base allowed another run to score on Jose Lobaton's RBI grounder as the Mets cut it to 3-2.
After Mets pitchers retired 16 in a row, Zimmerman's leadoff triple in the seventh got past a diving Bruce in right field, and Moises Sierra followed with a sacrifice fly to make it 4-2.
Zimmerman also hit a solo homer in the ninth.