“Tonight was a big game for us to have,” Mets manager Terry Collins said. “We weren’t supposed to win it. We had a rookie pitching. We have a rookie pitching tomorrow night. But that’s why it’s a great game — you just never know.”

The Mets took the lead for good in the third inning, on Granderson’s two-run single off Nationals starter Tanner Roark. That was all Roark allowed, but it was enough; the Mets tacked on a third run on James Loney‘s RBI double off Matt Belisle in the sixth.

Loney's RBI double

Loney’s RBI double

WSH@NYM: Loney rips an RBI double to right in the 6th

James Loney smacks a double to right field that plates Travis d’Arnaud, extending the Mets’ lead to 3-1 in the bottom of the 6th inning

Though the Nationals filled the basepaths all evening, their only run came on Anthony Rendon‘s sacrifice fly in the first. Gsellman scattered six hits, three walks and an error in six innings, and four Mets relievers did the rest. It hardly mattered that four Nationals hitters reached base multiple times — including Bryce Harper, who singled once and walked twice, but never scored.

“We had a few opportunities. We hit a couple of balls hard. [The Mets] had some opportunities, too,” Nationals manager Dusty Baker said. “That was a big hit Granderson got.”

Combined with the Cardinals’ loss in Cincinnati, the win moved the Mets within one game of a Wild Card spot. The Nationals still hold a comfortable 9 1/2-game division lead with 27 to play.

Driving in a pair: Going into the game with a .116 average with runners in scoring position — the league’s worst single-season mark since Melvin Upton Jr. batted .108 with RISP in 2013 — Granderson came through with a two-run single off Roark in the third. The hit gave Granderson 40 RBIs to go along with his 22 home runs.

“I do believe in him,” Collins said of Granderson. “I do believe he comes up with big hits. Tonight he did.”

No depth from Roark: Roark usually goes seven innings, but not this time, as he pitched five, allowing two runs on five hits. His toughest inning was the third, when he gave up the two-run single to Granderson.

“I wasn’t pitching in the strike zone effectively,” Roark said. “It was not a good outing in my mind. I was not getting ahead, is the main thing.”

Roark fans Gsellman

Roark fans Gsellman

WSH@NYM: Roark strikes out Gsellman in the 4th

Tanner Roark strikes out Robert Gsellman on a foul bunt to end the bottom of the 4th inning

Cutting through the heart of the order: Tensions heightened in the seventh inning, when Jayson Werth singled with one out to bring Daniel Murphy to the plate in a two-run game. In came rookie left-hander Josh Smoker, who served up a sharp line drive to center, but Michael Conforto made a diving play to snare it. Smoker then struck out Harper on four pitches, the last of them a slider in the dirt that had Harper flailing.

Smoker's clutch strikeout

Smoker’s clutch strikeout

WSH@NYM: Smoker strikes out Harper in the 7th

Josh Smoker strikes out Bryce Harper swinging in the top of the 7th in his first appearance against his former team

“That’s a tough situation right there,” Conforto said. “If that ball gets past me, Werth probably scores from first. But with the jump that I had and the way the ball was carrying — Murph hit that ball really hard — I felt like I had an opportunity to go down and get it. It definitely felt good to get that one and keep Murph off the bases.”

Conforto's amazing catch

Conforto’s amazing catch

WSH@NYM: Conforto makes a spectacular catch in center

Michael Conforto races in on a line drive and makes a terrific catch in center field to rob Daniel Murphy of a hit in the 7th inning

Leaving ’em stranded: The Nationals went 0-for-7 with runners in scoring position. Their biggest chance to score came in the sixth inning, when they had runners on first and second with no outs. After Ryan Zimmerman grounded out to advance the runners one base, Danny Espinosa struck out swinging and pinch-hitter Ben Revere grounded out to end the threat.

Gsellman escapes trouble

Gsellman escapes trouble

WSH@NYM: Gsellman induces grounder to end threat

Robert Gsellman gets Ben Revere to ground out to strand runners on second and third in the top of the 6th inning

“It means a lot. It’s definitely fun baseball to be a part of. Hopefully, we can pull it out.” — Gsellman, on his role in the Mets’ playoff chase

With a single in the first inning, Murphy extended his hitting streak against the Mets to all 15 games he’s played against them this season. That matches Tony Gwynn for the longest streak against the Mets to start a career with a team.

After Loney’s double in the sixth inning, Oliver Perez entered in relief and grazed Kelly Johnson‘s hand with his first pitch. Baker challenged the play, but the call stood.

Johnson is hit by pitch

Johnson is hit by pitch

WSH@NYM: Johnson reaches on HBP, call stands

Kelly Johnson is hit by a pitch in the 6th inning and the call stands after the Nationals challenge

Nationals: On Saturday afternoon, Baker had a change of heart about who will pitch on Sunday night at Citi Field, so instead of right-hander Max Scherzer getting the nod against the Mets, right-hander Reynaldo Lopez will take the mound at 8:08 p.m. ET and face New York for the first time in his career.

Mets: A pleasant surprise for a pitching-starved team, Seth Lugo will take the mound for the 8:08 p.m. ET series finale against the Nationals. Since joining the rotation in place of Steven Matz, Lugo is 2-1 with a 2.55 ERA, holding opposing hitters to a .226 average.

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This story was not subject to the approval of Major League Baseball or its clubs.

Source: Mets News / Grandy, Gsellman give Mets Wild Card boost