LI's Alex Cirillo in the trenches as a producer of Derek Jeter docuseries 'The Captain'

Alex Cirillo has been in the film business for a long time, but she never before had her Yankees-fan husband weigh in on the creative process .  .  . or had a huge fan club show up at a screening at Yankee Stadium.

“There were about 3,000 people there, and about 300 of them were my friends and family from Long Island,” she said with a laugh in an interview with Newsday.

Such are the benefits of being a lead producer on “The Captain,” ESPN’s seven-part documentary on Derek Jeter.

“I think a project like that impressed my parents and made them feel proud,” she said. “You know, getting to say, ‘Hey, invite your friends and your siblings to come to Yankee Stadium and watch the first two episodes of my show!’  ”

As for her husband, Anthony Ferreiras, let’s just say he was more engaged in her work than is customary.

“Usually I’m doing an independent film about, you know, women’s issues,” Cirillo said. “And that’s not something that I ask him to watch with me all the time.

“It was really awesome to be able to have him by my side throughout the process .  .  . It was a great litmus test for what the audience and what Yankees fans would be excited about or would think was something new.”

Cirillo had a bit of a Yankees dynasty learning curve, because she grew up in a Mets-centric home in Rockville Centre.

Cirillo herself was active in sports and was coached in basketball by her father, Ray, who later was an assistant women’s basketball coach at Briarcliff College.

But after deciding that at 5-4, her future was not in the WNBA, Cirillo went into the film business, where she crossed paths with Randy Wilkins.

The two worked together on a short film about Jackie Robinson for MLB, and when Wilkins was named director of the Jeter series, he asked Cirillo to join him.

She said she worked as his “right hand,” notably setting up nearly every one of the 90 or so interviews in the series.

“It was easier than you would think, because it’s Derek Jeter,” Cirillo said. “We didn’t come up against a lot of resistance. People were excited to participate and to be asked to participate.”

Michael Jordan was willing but logistical complications delayed his sitdown until this spring, very late in the production process.

“He was super-generous and super-charismatic and really complimentary of Derek,” Cirillo said. “You could tell that their relationship is genuine and it wasn’t just a [famous] face we were interviewing, someone that people would be excited about. They have a genuine friendship. So he had real insight to share.”

Working with colleagues such as producer Gabe Honig and Wilkins, Cirillo got to sit in on at least parts of most interviews and said Wilkins was good about seeking their input. (By the way, line producer Jenna Carey also is from Rockville Centre.)

Cirillo, who has been in the business since 2008, said, “The Captain” is “by far” the biggest project she has worked on in terms of her role and the series itself.

“This wasn’t like slapping my name on as a producer on it; we were in the trenches all day, every day, and still to this day,” said Cirillo, who now lives in Oceanside.

What was it like working with Jeter himself?

“I didn’t really know what to expect,” she said. “He’s this legend, and at the end of the day, I felt like he was as much a normal guy as such a champion could be.

“But what really struck me was how he has the mindset of a champion and he can’t turn that off. So as much as he will chitchat with you about life or the weather, there’s this edge to him, this competitive edge that is so unique to someone who is as successful as he is.”

Cirillo said Wilkins sought a crew that not only was diverse in race, age and gender but in fandom. He did not want everyone to be like him — a guy from the Bronx who grew up a fan of the Yankees and Jeter.

Cirillo knows both sides of the Mets/Yankees coin. She said the reaction of family and friends at the screening confirmed what the project is all about.

“It was really special to hear how nostalgic they were watching episodes one and two and how it brought back memories of going to games with their parents and their grandparents, and a lot of them are new parents now,” Cirillo said,

“I got a lot of really touching personal stories from people who just felt like these moments that were included in the film were seminal moments in their youth as New York sports fans.”

By Neil Best

neil.best@newsday.com@sportswatch

Neil Best first worked at Newsday in 1982, returned in 1985 after a detour to Alaska and has been here since, specializing in high schools, college basketball, the NFL and most recently sports media and business.