It was the alternate universe of the Mets' nightmares. For the Yankees, it was one step closer to the dream scenario they need to snatch the AL East title from right under the Blue Jays.

The sixth inning of the Yankees' 11-2 win in the rubber game of the Subway Series at Citi Field on Sunday night gave the Mets their first true taste of a world without Matt Harvey: five runs allowed, two errors and a big, booming three-run homer by Dustin Ackley. Their lead was gone, the Nationals had already won, and about every Mets fan in the stands began fretting like it was 2007.

The Yankees, meanwhile, drew to within 2 1/2 games of first place and inch their way to avoiding a one-game play-in.

Harvey, who was on a strict innings limit, cruised through five, striking out seven, allowing one infield hit, a walk and nothing else before dejectedly huffing and puffing his way to the bench. And the Yankees, stymied and desperate to gain on the Blue Jays, who had lost to the Red Sox earlier in the day, were more than primed to pounce.

With Hansel Robles in for Harvey, Jacoby Ellsbury hit a ball to second base that Daniel Murphy barehanded and threw away for an infield single and an error. Brett Gardner tried to sacrifice Ellsbury to third, but Robles attempted to cut off the lead runner, and threw to David Wright, who dropped the toss. An old-school collapse seemed imminent, and the new-school Mets, nursing a one-run lead, obliged.

Carlos Beltran doubled to the wall in right-center -- a ball that Juan Lagares failed to get a good jump on -- and both runners scored. Beltran advanced to third on a wild pitch, Greg Bird walked and, with two outs, Ackley hit a fastball to right for a three-run homer and a 5-1 lead.

Erik Goeddel walked Chase Headley with the bases loaded in the seventh and the Yankees tacked on five more in the eighth, three of those coming on a Greg Bird homer.

"It's hard" to sit your pitchers, a prophetic Terry Collins said before the game. "We've waited since I've been here, so we've waited five years to be in this situation and now you've got your No. 1 pitcher, who you've got to watch what he does . . . in a pennant race. But it's the best for all of them. It's the best for the organization. So you suck it up and move on and get ready for the next day."

The Mets got on the board in the first inning, when Ruben Tejada, leading off for only the second time this season, doubled off CC Sabathia. Three pitches later, he was crossing home plate, courtesy of a Wright double to right-center.

Sabathia was otherwise untouchable. He went six innings, allowing that one run, five hits, three walks and striking out seven.

Meanwhile, Harvey had things firmly in hand . . . for as long as he was in the game. He struck out the first two batters to face him, both on 1-and-2 counts and both swinging. Ellsbury whiffed on a two-seam fastball, while Gardner went down on a curveball to pace Harvey to a compact 11-pitch first.

Harvey didn't allow his first hit until the third, when Gardner reached on an infield single to put runners on the corners with two outs (Ellsbury previously reached on an error and stole second). Harvey then battled Beltran, who fought off everything the righty had to offer before flying out to right on the 10th pitch of the at bat. He then retired the side in order in the fourth, aided by strikeouts of Brian McCann and Headley.

Harvey threw 77 pitches, 51 strikes. But that doesn't much matter, Collins said. "When he reaches the innings limit that we set, he's out," he said. "Whether it's 40 or 85 [pitches], it ain't going to matter."

That's the world the Mets must live in now, a world with Matt Harvey, but not enough of him to go around.