NEW YORK -- Wilmer Flores' night began in unexpected fashion Friday, when the New York Mets second baseman got a standing ovation for making a diving stop of a first-inning grounder by Washington Nationals third baseman Yunel Escobar.

"I didn't anticipate that," Flores said.

Neither Flores, nor anyone in a Mets uniform, nor even the greatest scriptwriter in Hollywood could have anticipated how Flores' night would end.

Flores, who wept on the field Wednesday night because he thought he was about to be traded, capped a whirlwind week for him and a potentially season-defining day for the Mets by hitting a leadoff homer in the 12th inning to lift New York to a 2-1 win over the Nationals in front of a frenzied crowd of 36,164 at Citi Field.

"I'm sitting here looking at some guys who are outstanding writers," Mets manager Terry Collins said afterward. "You couldn't write that. You guys couldn't come up with that. And you're good. That's unbelievable."

The homer to left-center field by Flores ended a marathon pitcher's duel in the opener of a three-game series and pulled the Mets (53-50) within two games of the Nationals (54-47) in the National League East.

"Can it happen at a better time to a better person in a bigger situation than that?" Collins said. "We are all so thrilled for him. It's unbelievable."

The trade that would have sent Flores, along with injured right-handed pitcher Zack Wheeler, to the Milwaukee Brewers in exchange for center fielder Carlos Gomez fell apart at the last second late Wednesday night, but not after news about it trickled out and everyone in the Mets dugout and in the stands thought Flores was getting traded.

Flores continued to play in the game Wednesday because Collins hadn't been informed of the impending trade. Television cameras captured the 23-year-old, who signed with the Mets as a 16-year-old out of Venezuela, crying at shortstop in the eighth inning.

"Two days ago, a lot of phone calls and a lot going on," Flores said.

Flores' emotional reaction endeared him to Mets fans, who loudly applauded his name when it was read with the rest of the starting lineup. He got another warm ovation when he stepped to the plate for the first time in the second inning.

"What they did for Wilmer Flores, you're not going to find in a lot of places," Collins said. "That is the most respectful way to handle a situation that these fans can possibly come up with."

Flores accounted for the Mets' first run with an RBI single in the fourth. A trio of Mets right-handed pitchers – Jeurys Familia, Hansel Robles and winning pitcher Carlos Torres – retired 11 straight between the ninth and 12th, including the last five by strikeout, before Flores hit a 1-1 pitch from right-hander Felipe Rivero (1-1) over the left-center field wall.

"Words can't really describe what has been going through his head and us as a team the last couple days," said right-handed pitcher Matt Harvey, who retired the first 16 batters he faced and allowed one run and five hits while walking none and striking out nine in eight innings.

"Everything that has happened to him is pretty incredible. And for tonight to happen the way it did, it's pretty unreal."

Flores' expression didn't change much as he rounded the bases, but he broke into a wide grin upon nearing home plate and flinging his helmet in the air before he was mobbed by teammates.

"Great feeling," a still-smiling Flores said afterward. "Game over. We won. Let's cheer."

After Flores touched home plate, the scoreboard, which flashed multiple promotions touting Cespedes' arrival and fireworks night on Saturday, flashed the words GO WITH THE FLO. On this night, the Mets were sure glad they did.

"As the game went on, we said one thing: There's one guy we're not going to hit for tonight," Collins said with a laugh. "Wilmer Flores."

For the Nationals, Escobar had an RBI single in the eighth when Washington built a two-out rally against Harvey via a hit batsman and two singles.

"It's one game," Nationals manager Matt Williams said. "It could have been a 3-1 game in nine (innings). It counts the same."

A trio of Nationals relievers -- Rivero as well as right-handers Tanner Roark, Aaron Barrett and Rivero -- had to account for 6 1/3 innings after left-hander Gio Gonzalez lasted just 4 2/3 innings. Gonzalez allowed one run, four hits and four walks while striking out six in his second shortest start of the season.

"We extended guys in the bullpen," Williams said. "See if we can make an adjustment on that tomorrow."

NOTES: The Mets will have OF Yoenis Cespedes in uniform for Saturday's game. Cespedes was in Baltimore with the Detroit Tigers but couldn't get to Queens in time to play Friday because the trade wasn't completed until just before the 4 p.m. deadline. ... Cespedes will continue to wear No. 52 for the Mets. RHP Carlos Torres, who wore No. 52, will switch to No. 72. ... After Thursday's game, the Mets made room for C Travis d'Arnaud by optioning C Anthony Recker to Triple-A Las Vegas. ... Nationals RF Bryce Harper went 0-for-5 and was ejected for arguing with home plate umpire Jerry Meals after an 11th-inning strikeout. ... Nationals RHP Stephen Strasburg (left oblique strain) is expected to make his final rehab start for Triple-A Syracuse on Monday.