NEW YORK -- Like a lot of summertime sequels, the July 2016 edition of a New York Mets-Washington Nationals series hosted by the Mets was missing a lot of ingredients from the original.

However, with the star still in place, people still exited the theatre -- or, in this case, Citi Field -- happy.

Wilmer Flores continued his torrid stretch, as well as his knack for delivering clutch hits against the Nationals, by crushing the go-ahead, three-run homer in the bottom of the fifth inning Thursday night, and the Mets earned a wild 9-7 win in the opener of a four-game series.

The Mets (47-38) are 7-1 in the first eight games of an 11-game homestand, and they moved within three games of the first-place Nationals (51-36) in the National League East. Washington led by six games on June 29, the day it capped a three-game sweep of New York at Nationals Park.

"We fell so far behind when we went in there and got swept," Mets manager Terry Collins said. "I just thought, coming into this homestand, that we had to make up some ground."

The Mets' charge to the 2015 National League pennant began last July 31, when Flores -- who was nearly traded to the Milwaukee Brewers two days earlier -- hit a walk-off homer in the 12th inning to give New York a 2-1 win over the division-leading Nationals.

"That was the first thing I thought of -- God, this guy gets huge hits against these guys in big situations," Collins said.

The Mets went on to win the final two games of the series to create a tie for first place in the NL East before moving into first place for good Aug. 3.

"The games are a little similar because (this is) an important series," Flores said.

Flores didn't start Thursday but entered in a double switch in the top of the fifth, when Collins pulled right-hander Bartolo Colon with two outs and the Mets down 6-4.

Asdrubal Cabrera and Brandon Nimmo opened the bottom of the fifth with singles before Travis d'Arnaud struck out. Flores hit the first pitch he saw from left-hander Oliver Perez (2-2) deep into the first deck in left field for his fifth homer in five games, a stretch in which he is 10-for-18 with 10 RBIs.

"I was just ready for him," Flores said. "I faced him a couple times. First pitch that I saw, I put a good swing on it."

The homer by Flores capped a frenetic two-inning span in which the Mets and Nationals combined for 11 runs on 15 hits, including six homers.

Solo blasts by Bryce Harper, Clint Robinson and Anthony Rendon gave the Nationals a 4-1 lead in the top of the fourth before the Mets tied it in the bottom of the inning on solo homers by d'Arnaud and Jose Reyes and an RBI double by Yoenis Cespedes.

The Nationals took the lead again in the top of the fifth, when Daniel Murphy -- who signed with Washington after winning NL Championship Series MVP honors for the Mets last October -- beat out a potential inning-ending double play as Perez scored. Murphy was initially ruled out, but the Nationals successfully challenged the call. Wilson Ramos delivered an RBI single two batters later to extend the lead to 6-4.

"This kind of was a heavyweight bout today," said Mets second baseman Neil Walker, one of five starters Thursday who was not with the club last season.

Cabrera homered in the sixth and Murphy homered in the seventh -- the teams combined for a Citi Field-record eight homers -- before Walker capped the scoring with an RBI single in the eighth.

"We fought back, they fought back," first-year Nationals manager Dusty Baker said. "Probably a heck of a game to watch, but a terrible game to lose."

Right-hander Hansel Robles (3-3), the third of six Mets pitchers, earned the win with 1 1/3 shutout innings. Addison Reed retired all four batters he faced before Jeurys Familia notched his 31st save with a hitless, albeit interesting, ninth.

Familia opened the ninth by walking Jayson Werth before Murphy hit a grounder to deep short. Cabrera made an impressive diving stop and threw to Walker, whose throw to first was not in time to get Murphy. However, the umpires ruled Werth slid past the bag and called both runners out.

Baker asked for a video review, which confirmed the original ruling.

"My contention was (Murphy) would have beat the throw no matter what," Baker said.

Curtis Granderson reached base five times in six plate appearances for the Mets. Murphy finished with three RBIs for the Nationals, who had five players record two hits apiece -- including Perez, who had his first two-hit game since May 2, 2007, when he was a member of the Mets.

Colon allowed six runs on 10 hits and no walks while striking out two over 4 2/3 innings. Nationals starter Lucas Giolito allowed four runs on seven hits and four walks while striking out four over 3 2/3 innings.

NOTES: Mets GM Sandy Alderson said RHP Matt Harvey has symptoms of thoracic outlet syndrome. Alderson said Harvey would likely decide this weekend whether or not to have season-ending surgery or receive a nerve-blocking injection in hopes of pitching again soon. ... Nationals 1B Ryan Zimmerman (general soreness) did not play. ... Nationals RHP Lucas Giolito was born July 14, 1994. Per research by Major League Baseball, the 43-year-old Mets RHP Bartolo Colon made a start for the Cleveland Indians' affiliate in the rookie-level Appalachian League the day before Giolito's birth.