It was a New York “Field of Dreams.”

A scrappy bunch of co-ed beer-league softball players thought they didn’t stand a chance of making it to last week’s playoffs in Hell’s Kitchen — that is, until a Yankee legend stepped up to the plate and turned them into winners.

It wasn’t the movie’s ghostly figment of Shoeless Joe Jackson who walked onto the field at Harlem River Park on East 128th Street 13 days ago to lead the beleaguered “Senior Circuit” team to a victory.

It was Mickey “Mick the Quick” Rivers — the former pinstripe centerfielder and twice-World Series champ of the ’70s.

“Here we are on the playing field, and to our amazement he comes by. It was like a scene out of “Field of Dreams,” said pitcher David Fischer, 41, a vice president of a hat company.

By chance, two players on the team had met the famed base stealer at a benefit in July right before the big postseason game.

“I figured there was nothing to lose,” said Evan Kleinman, a 43-year-old financial adviser from Manhattan who approached Rivers. “Who wouldn’t want Mickey Rivers coaching them?”

“It was unbelievable that he said yes. We never thought he would,” said Fischer, who stood in awe on the mound as Rivers suddenly appeared with his two sons under the Harlem stadium lights.

“He was hitting grounders before the game, and during the game he would direct the players on the field.

“He coached us as if this was the seventh game in the World Series. His energy, his intensity and kindness was so unreal. It was an amazing night,” said Fischer.

“I really believe that we won that game and made it into the playoffs because of him. It was not only his coaching, but we all wanted to do well in front of him. He was so supportive.”

But the 63-year-old Harlem resident, who still heads up to Yankee Stadium on occasion and makes appearances for his old team, shrugged, “I love the game and I love to teach.”

Last Wednesday Rivers coached the team in the first round of the playoffs at DeWitt Clinton Park in Hell’s Kitchen.

Rivers, who spent four-plus seasons in The Bronx, coached third base, maneuvering the defense, and giving hitting tips between innings.

Despite a fast start, with Fischer scoring on a double and a couple of errors, Senior Circuit’s season came to a nail-biter of an end, a 7-5, 10-inning defeat.

“He had tears in his eyes. He really wanted us to win,” said Fischer.

“I don’t like to lose. I don’t care where it is,” said Rivers.

“Most of the guys on this team grew up watching him play,” said Kleinman. “And for the guys and girls who are too young, they have dads and uncles who loved him. I can’t imagine how he finds our team remotely interesting, but to us, it feels like baseball fantasy camp. It’s one of the highlights of my life.”