New York Yankees manager Joe Girardi looks down during the...

New York Yankees manager Joe Girardi looks down during the eighth inning of a baseball game against the Boston Red Sox in Boston, Saturday, Sept. 17, 2016. The Red Sox won 6-5. Credit: AP / Michael Dwyer

The manager’s office inside the visitors’ clubhouse at Fenway Park has the ambience of a cinderblock cave, and with a desk clogging up most of the interior, that leaves Joe Girardi pinned against the wall for his postgame interrogations by the media.

As uncomfortable as that sounds under the best of circumstances, imagine how Girardi has felt during the past three days as he has watched the Yankees’ season begin to circle the drain. That sucking whirlpool picked up even more speed Saturday after a third straight loss to the Red Sox, this time by the score of 6-5, with the winning run scoring on a wild pitch.

When the Yankees first arrived at Fenway, they were four games behind the Red Sox with four to play against the AL East leader, and anything seemed possible. Heck, maybe taking a stab at the division title was within reach.

No longer. All of that hope has pretty much disintegrated, with even the wild card slipping away. Yet Girardi sat in that gloomy office, squeezed into that cement corner, and refused to budge one millimeter.

“Sure it’s tougher,” he said. “But people thought it was tough Aug. 1, didn’t they? All of a sudden we were one game back in the wild card. So yeah, we’ve got a lot of work to do, and we have to win a lot of games, but I’m not giving up.”

Not after four consecutive losses, not after losing six of seven and not after seeing Starlin Castro and Jacoby Ellsbury leave Saturday’s game with injuries severe enough to send them back to New York for more tests.

Castro pulled up lame on a sure double, clutching the back of his right leg between first and second, then later was diagnosed with a hamstring strain.

As for Ellsbury — not the quickest of healers — he had a scary collision in the centerfield triangle, slamming his right knee against the bullpen wall. Despite staying in to finish the seventh inning, he had to be replaced in the eighth because of a patellar issue.

Dropping games is one thing. Losing key players in the process is a more troubling issue to overcome, and Saturday’s double-whammy increases the degree of difficulty to a place the Yankees really can’t afford right now.

While they did an inspired job against $217-million man David Price, taking an early 5-2 lead with a boost from the Green Monster-clearing two-run homer by Gary Sanchez, the Yankees again couldn’t finish. Just like Thursday’s ninth-inning meltdown, the gut-wrenching loss that set the tone for this weekend.

“A lot’s changed in 48 hours,” Brett Gardner said.

But not Girardi, whose public stance rarely wavers regardless of how dismal things seem to get. When Brian Cashman traded a talented chunk of the Yankees’ roster right out from under him at the Aug. 1 deadline, essentially making Girardi the Scranton manager, he didn’t blink. Girardi also was the one left holding the bag on Alex Rodriguez, forced to answer the daily questions about his evaporating playing time until Hal Steinbrenner mercifully cut a deal to jettison him from the team.

While others couldn’t get their forks into this season fast enough, Girardi stood firm and insisted that his plan remained the same: to win games. No one believed him, but the Yankees have gone 25-19 (24-13 before their current 1-6 slide) since the team was stripped, its bullpen decapitated for the sake of the farm system. Girardi does deserve credit for that.

“We had a plug-and-play team that we felt was ready to compete out of the gate, and it didn’t work out that way,” Brian Cashman said. “We all made an audible and he’s adjusted well every step of the way. I think he’s done well.”

And it’s going to earn Girardi some Manager of the Year votes, no doubt about that. But there’s only so much he can do. The Yankees just aren’t good enough right now to qualify for the playoffs, to erase the expanding deficit, to outpace four other teams ahead of them in the wild-card race — even if Girardi chooses not to believe it.

“I don’t lose faith — that’s not who I am,” Girardi snapped. “I know some people do, but I don’t.”

Said the manager with his back against the wall, both literally and figuratively.

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