Jodie Foster and the Real-Life Swim Coach She Plays in Drama Nyad Bonded Over NFL and Card Games (Exclusive)

Bonnie Stoll has a saying she likes to repeat: “Don’t tell me, show me.”

So when the 71-year-old athlete and former racquetball pro heard rumblings about a possible movie that would dramatize how she coached her longtime friend, swimmer Diana Nyad — who made a record-setting 100-plus-mile journey from Cuba to Florida in 2013 — she brushed it off.

“I'm not sure that's the truth yet, blah blah blah,” she remembers thinking.

Then Oscar-nominated actress Annette Bening signed on to play the title role in Nyad, and Stoll began to get excited. The subsequent news that two-time Oscar-winner Jodie Foster would play Stoll had her truly elated.  

“I would think that anybody in my position would be thrilled,” says Stoll. “And she’s just the loveliest human being.”

Stoll says she and Foster had met previously in passing, but didn’t know each other well. Then her phone rang. “She called and said, ‘Can I come over?’” recalls Stoll, who lives in Los Angeles.

Stoll, who “has the demeanor of an exceptionally jovial drill sergeant,” as The New Yorker once put it, and Foster immediately hit it off. 

“I can't sit still for the most part. Jodie came over. We sat outside for three hours straight. I never even thought about standing up. You know, ‘What’s your favorite food?’ ‘Oh, me too!’ That kind of thing,” explains Stoll.

The women formed a friendship that continues to this day, and they hang out frequently. “We watch football. She’s a big NFL fan,” says Stoll, who says they also play a card game called Push. 

“Jodie, as bright as she is — and we all know how bright she is — she really is not a very good…[she] doesn't add well. I always have to count her points at the end after she counts them wrong!” says Stoll.

After all their time together, Foster mastered Stoll’s mannerisms for the movie, which follows Nyad’s multiple attempts to swim from Cuba to Florida when she was in her 60s. Nyad enlisted close friend (and her former girlfriend) Stoll, who had no experience as a swim coach, to guide her during the arduous process.

Never miss a story — sign up for PEOPLE's free daily newsletter to stay up-to-date on the best of what PEOPLE has to offer, from juicy celebrity news to compelling human interest stories.

The plan was for Nyad to swim while Stoll and their small but dedicated team stayed beside her in an escort boat, providing food and moral support on the journey, which would ultimately take 53 hours after several attempts.

Along the way, they faced inclement weather, dangers like sharks and jellyfish—not to mention doubters who thought it couldn’t be done.

Stoll assures that the movie is “99 percent accurate,” including the portrayal of Nyad’s strong personality.

“She can be prickly,” says Stoll. “Diana definitely had that determination and tunnel vision. People can see the determination and the attitude that she had, absolutely. But she appreciated every one of her teammates.”

After seeing the completed film, which is getting Oscar buzz for the performances, “I thought it was myself up there,” Stoll says of seeing Foster onscreen. “Every single person [who sees the movie], the first thing they'd say is, ‘Boy did she nail you,’” she continues.

As for the awards chatter around the movie, Stoll isn’t letting herself fantasize about Oscar glory just yet. “Don’t tell me,” she says. “Show me.”

Nyad, directed by Elizabeth Chai Vasarhelyi and Jimmy Chin, the filmmakers behind the Oscar-winning 2018 climbing documentary Free Solo, is streaming on Netflix Friday.