It might be hard to tell from the meager body count in the seats at Citi Field, but suddenly, Mets games in September have taken on some meaning. Call the wild-card chances of a sub-.500 team a major long shot if you like, but if nothing else, it's a valuable experience for a young team full of promising arms for the future.

Coming off eight shutout innings by Rookie of the Year candidate Jacob deGrom in Tuesday's win over the Rockies, rookie Rafael Montero stepped in as a spot starter Wednesday night and took a no-hitter into the fifth inning of what became a 2-0 victory.

Montero's spell was broken when he gave up a double to pitcher Tyler Matzek with two outs in the fifth, but the Mets completed a sweep of the Rockies and tied their season high with a fourth straight victory and seventh in eight games.

The Mets remained 5½ games behind Pittsburgh, which holds the second wild-card spot and won at Philadelphia. But they have 16 games left to gain ground, starting with a four-game series against NL East leader Washington that opens Thursday night at Citi Field.

"We've still got a tough road ahead,'' manager Terry Collins said. "We have the Nats coming in, who play absolutely great here. We've got our work cut out for us.

"But when you walk through the clubhouse doors in September, even though you're looking at a wild card, you're still playing for something. It's fun to go out there and compete.''

Montero (1-3) had a rough time in May, spent most of the summer at Triple-A Las Vegas and had not started since Aug. 17. He began with two strikeouts followed by two walks, which set the tone in terms of pitch volume and the absence of Rockies offense.

The Mets took a 1-0 lead in the second after Dilson Herrera drew a two-out walk and scored on a triple to center by Eric Young Jr., whose three hits tied his season high.

With two outs in the fifth, Montero walked DJ LeMahieu before Matzek (5-10) drilled his double over Young in left. But Young's throw held LeMahieu at third before Montero got a fly ball to end the threat.

As Montero approached 100 pitches, he gave up a leadoff double to Drew Stubbs in the sixth, followed by a single by Justin Morneau. Montero recorded his seventh strikeout against Nolan Arenado and was relieved by Dario Alvarado, who got the only batter he faced before Carlos Torres induced a pop-up to preserve the 1-0 lead.

Montero threw 106 pitches, and Collins said, "We've got to fix that. His stuff plays, as we've seen, but we've got to stop getting him in those deep counts because he's going to run into problems. But tonight, he made some really good pitches and had good movement.''

The rookie brushed aside worries about pitch counts and celebrated his first big-league win in his seventh start. "I feel pretty good,'' Montero said through an interpreter. "If I continue to pitch the way I did tonight, there will be more to come.''

Jenrry Mejia was lifted Tuesday night after loading the bases with one out. He put that behind him with a 1-2-3 ninth to record his 25th save.

"It's huge for him,'' Collins said. "He came to me today and said, 'I want to get back in there.' I love that.''