WASHINGTON -- T.J. Rivera, the Pacific Coast League batting champion who started this game on a hunch by Mets manager Terry Collins, hit his first career homer in the 10th inning to lead New York to a 4-3 victory Tuesday night at Nationals Park.
Rivera's homer came on an 0-2 pitch from Nationals closer Mark Melancon, who surrendered a homer for the first time in 22 games with Washington. With the win, the Mets maintained their half-game lead for the second National League Wild Card spot, as the Cardinals also won on Tuesday; the Mets gained on the Giants, who lost Tuesday night and saw their lead for the first Wild Card spot fall to a half-game.
"Somebody's got to surprise you," Collins said. "Somebody you don't expect has got to come through, and tonight it was T.J."
After a quiet night on offense, the Nationals forced extra innings with a two-run rally in the ninth off Mets closer Jeurys Familia aided by an error from José Reyes and some weak contact that turned into hits.
"We came back. The mark of a champion is when you figure out a way to win and come back," Nationals manager Dusty Baker said. "Even though we lost that game, it's going to go a long way with us in our quest for the championship."
New York nearly spoiled a dominant outing from right-hander Noah Syndergaard, who put together another strong start in his case for the National League Cy Young Award. He struck out 10 batters in seven innings to record his first double-digit strikeout game since June.

Washington's magic number remains at nine after right-hander A.J. Cole, who was making his fifth start in place of the injured Stephen Strasburg, spent most of the night pitching out of trouble. He allowed three runs on nine hits and issued a pair of walks in five innings, although he did strike out six.
MOMENTS THAT MATTERED
Unlikely contributions: It was Rivera who first broke through for the Mets, lacing an RBI single in the third inning to tie the game at 1. But his most significant contribution was the home run that he yanked over the left-field fence in the 10th, giving the Mets the lead mere moments after they lost it. A surprise inclusion into the starting lineup, Rivera added a sacrifice fly in the fifth inning, finishing 3-for-4 with three RBIs to increase his average to .333.

"[My mindset] is definitely not to try to hit a home run," Rivera said. "I try to play my game and put the bat on the ball consistently. That was really my main focus that whole at-bat, was to compete. … Great feeling, but better feeling when we finished it off." More >
Ground-ball rally: It would be difficult to blame Familia for his blown save in the ninth. The Mets' closer coaxed four straight ground balls to open the inning, beginning with a slow roller that Daniel Murphy beat out for an infield single. The next batter, Bryce Harper, sent a ground ball to third base, where Reyes fielded it but threw wide of first. An Anthony Rendon grounder through the infield and a Wilson Ramos chopper back to the mound tied things, still with no outs, but the Nationals could not scrape across the game-winning run.

"We've got arguably the best closer in the game, and he got four ground balls -- three of them didn't even get out of the infield -- and the game's tied," Collins said. "He was frustrated about it and we certainly understand it, but we wouldn't be sitting where we are without him."
"I thought we grinded at-bats all inning," Murphy said. "Put ourselves in a really good spot there. We were able to tie it up, and I think first and second with nobody out. Clint [Robinson] hits one right on the button right there, could've won it right here."
Nobody's perfect: Of course it was Murphy -- who else? -- who came to the plate with a man on first base and two outs in the 10th inning, an extra-base hit away from tying the game yet again. With Familia already back in the clubhouse, the Mets turned at that point to lefty specialist Jerry Blevins, who struck out Murphy to record his first save since 2012. It was Murphy's 56th strikeout in 136 games.

"If you don't get excited for moments like that, you're in the wrong sport," Blevins said. "Murphy's one of the best hitters in the game, and that's a challenge. Those are moments where you have to stand up. Those are the things you do as a kid in the backyard."
SOUND SMART WITH YOUR FRIENDS
Syndergaard's strikeout of Danny Espinosa in the fifth inning was the 200th of his season, making him the youngest Met since Sid Fernandez in 1986 to reach that mark. Only Fernandez, Dwight Gooden, Jon Matlack and Tom Seaver struck out 200 or more in a season before their 25th birthdays, though Syndergaard did not stop there. He finished with his fifth double-digit strikeout game of the season, allowing one run in seven innings.

"It's just an individual accolade to me," Syndergaard said. "It's cool. I just try not to focus on the result over the process."
Melancon had been nearly unhittable on 0-2 counts this season, with opposing hitters batting just .080/.080/.120 with 14 strikeouts in 25 at-bats against him.
"You know, tip your cap," Melancon said. "Good swing on it. You always learn from your mistakes. That's not going to affect me going forward. Sometimes, those wake-up calls can be a good thing."
Murphy continued to punish his former team with a double in the sixth inning, giving him a hit in all 18 games against the Mets this season, the longest single-season hitting streak against New York in history. After a pair of hits Tuesday, including starting the game-tying rally in the ninth, Murphy is now hitting .411 (30-for-73) with seven homers and 21 RBIs against the Mets this season. More >

WHAT'S NEXT
Mets:Robert Gsellman, one of the Mets' multiple rotation fill-ins, will return to the mound for a 4:05 p.m. ET series finale Wednesday at Nationals Park. Over his first three starts, Gsellman has posted a 1-1 record and 4.76 ERA, with 15 strikeouts against six walks in 17 innings.
Nationals: Tanner Roark will look to continue his stellar season as the Nationals wrap up their season series with the Mets. In three appearances (two starts) against New York, Roark has posted a 1.88 ERA.
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