New York Yankees general manager Brian Cashman talks with the...

New York Yankees general manager Brian Cashman talks with the media prior to a game against the New York Mets at Citi Field on Monday, Aug. 1, 2016. Credit: Jim McIsaac

The fact that Brian Cashman delivered the Yankees’ concession speech only minutes before the start of the Subway Series — at Citi Field, of all places — made what he had to say feel even more surreal.

For the record, the Yankees raised the white flag on their 2016 season at 3:42 p.m. Monday, when Carlos Beltran’s trade to the Rangers became official. Beltran, a former Met, said his farewell outside the visitors’ clubhouse and then was gone, off to play for the seventh team in his 19-year career.

“We’ve been contending for a long, long time,” said Cashman, whose team reached the playoffs in 18 of the previous 21 seasons. “We’re damn proud of that. From my perspective, there’s no shame in anything we’ve done today. We’ve made good, sound business decisions. We’ll see where it takes us.”

Down the hallway, the Mets had just completed a deal for Jay Bruce, the hitter they hope can keep them afloat in the National League wild-card race. Both Cashman and Sandy Alderson had worked to exhaustion before the 4 p.m. non-waiver trade deadline, just toward opposite goals.

Cashman’s sell-off, capped Monday by Beltran and Ivan Nova, imported a dozen prospects, including four first-round draft picks, but they were postmarked for Scranton, Trenton or Tampa instead of the Bronx. Turns out the Yankees didn’t need any of them Monday night to beat the Mets, 6-5, in 10 innings.

The strange thing? It was one of the Yankees’ more inspired wins. Brett Gardner led off the game trying (unsuccessfully) for an inside-the-park home run. We saw an actual fist pump from the stoic Jacoby Ellsbury. Austin Romine stole a base for the first time since 2013. And the Yankees rallied late against the Mets’ usually bullet-proof setup man, Addison Reed.

“I thought the effort was great,” Joe Girardi said.

Still, if any New York team plays in October this season, it will be the Mets, a franchise that is painfully familiar with what lies ahead for the Yankees during the next two months and beyond.

The Mets’ own rebuilding effort took more than five years and culminated in last October’s World Series loss to the Royals. In their current state, they’re a long shot to return after being a favorite on Opening Day. And while the trade for Bruce should provide an offensive jolt, it doesn’t have the feel of the Yoenis Cespedes stunner a year ago. Even Alderson had to admit that Bruce, a lefthanded-hitting corner outfielder, “is not an absolute perfect fit for us.”

The Mets also went down to the wire angling for Jonathan Lucroy but were rebuffed in the final hour when the Brewers traded him to the Rangers. Bruce brings 25 homers and his NL-leading 80 RBIs, but expecting another Cespedes-type boost might be asking too much.

“Look, it was an extraordinary turnaround last year,” Alderson said. “All we can do is try to acquire as many good players as we can to put ourselves in a position to maybe have that magic again.”

It was an odd juxtaposition: the Mets talking about a playoff push and the Yankees discussing what sabotaged a season that already was kaput, aside from the chance to evaluate the parade of youngsters heading to the Bronx. Cashman now is presiding over the franchise’s first makeover since the 1980s, a process he hinted was kick-started by getting swept by the Rays over the weekend. Because every trade requires Hal Steinbrenner’s approval, Cashman suggested his superiors were swayed by the team rolling over days before the deadline.

“I think it influenced the people above me more,” Cashman said. “The inconsistency of our club reared its ugly head. A true playoff contender wouldn’t have done that.”

So what now? As demoralizing as the trade of Andrew Miller was, dealing Beltran — the Yankees’ most dangerous hitter — told everyone in the clubhouse that they’re on their own. And good luck with that.

Girardi said people probably think he’s “delusional” for believing these depleted Yankees can win. On Monday night, the Mets, for all their playoff aspirations, were not among that crowd.

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