Top, “Curveball” by Martha Ackmann, shown above. At left is a poster for “Toni Stone” by the Roundabout Theatre Company.
Top, “Curveball” by Martha Ackmann, shown above. At left is a poster for “Toni Stone” by the Roundabout Theatre Company. Credit: Contributed photo/James Gehrt

Many writers and performers dream of making their way to Broadway at some point in their careers. Martha Ackmann of Leverett had no such plan. Nevertheless, an adaptation of one of her books, “Curveball” (2010), is about to open in New York.

The play, adapted from Ackmann’s book by award-winning playwright Lydia Diamond, is called “Toni Stone.” Stone (1921-1996) was the first female player in baseball’s Negro League. She faced formidable obstacles and broke barriers as an African American and as a woman.

I sat down recently with Martha Ackmann to talk about Toni Stone, Broadway, and Ackmann’s work in general. I asked how she happened upon Stone’s story.

“I knew I wanted to write a baseball book,” she explained. “I’m a sports fan, and I very much believe sports is a view into the nation. I knew baseball best. I was raised in a baseball family. … I had heard this phrase, ‘the woman who replaced Henry (Hank) Aaron.’ I started digging.”

She found the story of Toni Stone. Stone was brought into the Negro League in the late 1940s. As the major leagues began to integrate, African-American teams looked for gimmicks that would keep fans coming to the ballpark. A female player sounded like a clever marketing ploy.

According to Ackmann, Stone knew she was brought into professional baseball as a novelty, but she was a skilled athlete who loved the game. She played her heart out.

By the time Ackmann began looking into Stone’s story, she recalled, the pioneering player was dead. “I had to work really hard at the research,” she noted, pointing out that documents about the Negro League don’t enjoy the same kind of archival collections as those from the major leagues.

“I had to find old guys who played with Toni,” said Ackmann, “and that was a delight. I spent a lot of time in garages and basements (across the country).”

“Curveball” was well received, but its author had no idea that it would eventually become a play.

“I did a lot of media with ‘Curveball,’” she informed me. “I had done a segment for ESPN.

“A theater producer, Samantha Barrie, is a sports fan, rabid about baseball. She had always been looking for a good story. One morning she was putting on her makeup, and her makeup mirror was positioned so she could watch ESPN.”

Hearing Martha Ackmann talk about Toni Stone inspired Barrie to get in touch with Ackmann’s agent, and the process of forming the play began. It took seven years for Barrie to assemble a team for the play and to arrange for the workshops that helped shape it.

Eventually, Barrie found a home for “Toni Stone” at the Roundabout Theatre Company, one of New York’s premiere theatrical repertory groups.

Previews will begin at Roundabout’s Laura Pels Theatre on 46th Street tonight, May 23. The show officially opens on June 20 and will run through Aug. 11. It stars April Matthis as Toni Stone.

When I spoke with Ackmann in early May, she had just returned from sitting in on table readings of the play in New York.

“It’s been just thrilling,” she enthused. “I was down there most of the week for rehearsals. They are so exciting … and so exhausting.”

She confessed that she had expected to serve merely as a witness but ended up being consulted by the cast and crew.

“Frequently, they were asking for some kind of context,” she elaborated. “‘Are we talking about exhibition games or are we talking about barnstorming? Did Toni ever want to have children?’ I was busier with answering than I thought I would be.”

She added that she was careful to recognize the contributions of playwright Lydia Diamond, who has become a friend, and the hard work put in by the cast. “I’m very conscious of realizing that it’s Lydia’s script. I want to give her a lot of respect and a lot of space,” said Ackmann.

“When I left, I was saying goodbye to some of the actors and saying, ‘Boy, your work is hard.’ They said, ‘You haven’t seen it. Next week we have to stand up.’”

Ackmann explained that she was delighted by the creative team, which includes a choreographer for movement (Camille A. Brown, recently nominated for a Tony Award). The producers have also added elements of music and jazz to the story.

Ackmann finds those additions delightful and appropriate. “The Negro League ballplayers and the jazz musicians traveled the same circuit,” she told me. “It was known as TOBA: ‘tough on Black asses.’”

Ackmann acknowledged that adaptations don’t always thrill the authors of the adapted works. “This is my first time, and I’m just a lucky duck,” she said with a smile.

“Lydia can go places that I could not as a nonfiction writer. For example, in the Jim Crow South, Toni and the team could not stay just anywhere.

“It turned out that one time when Toni got off the bus, dead tired at night, the-boarding house proprietor took one look at her with 29 men and assumed she was a prostitute. Toni was devastated.

“She ended up staying in a brothel, where she discovered, as she said, good girls who took care of her.

“There was no way in the world that I was going to find that brothel. I told the story as it was told to me. I couldn’t go any further. In the play, Lydia (Diamond) has invented a character called Millie.”

The prostitute Millie becomes not only a vehicle for embellishing the story but develops into Stone’s first female friend, Ackmann explained. “That’s a whole area (of the play) that is very different from the book but that I think is very true to the spirit of the book.”

Ackmann recently retired from teaching at Mount Holyoke College after 30 years. “It was a good round number,” she reflected of her tenure at the women’s college. “I had a wonderful teaching career there and in particular wonderful students, but I’m very glad to return to my first love, which is writing.”

Her next book, “Vesuvius at Home,” is due out in February from W.W. Norton. It will focus on 10 days in the life of Emily Dickinson that changed the poet’s life.

Ackmann’s book project after the next may revolve around a living figure. Dolly Parton has fascinated the writer for a long time. “I want to take Dolly Parton seriously, and she hasn’t always been taken seriously,” stated Ackmann.

She plans to go to Nashville in October when Parton will celebrate her 50th anniversary at the Grand Old Opry with a concert. Ackmann said that she hopes to write a magazine article about the occasion that may serve as a springboard for a book.

Parton is in many ways a contrast to Toni Stone. As Ackmann put it, the veteran country superstar is “alive and very controlling — and rightly so — of her image and access.”

Another adaptation of Martha Ackmann’s nonfiction is also in the works. Actor Bradley Whitford has optioned the author’s first book, “The Mercury 13.” This 2003 work explored a little known 1961 program in which NASA tested a group of skilled American women with an eye to sending them into space.

Whitford, best known for his work on “The West Wing,” hopes to turn the women’s story into a television mini-series in conjunction with producer Amy Pascal. Ackmann reported that this project is in development and is “chugging along.”

It might seem to the casual reader that Ackmann’s subjects — would-be astronauts, a pioneering African-American baseball player, the Belle of Amherst, and a country-music legend from Tennessee — have little in common.

Martha Ackmann disputed this impression. “I’m always telling a similar story,” she argued. “I’m always trying to get at ‘what is America’ through the lens of looking at women, women who are pushing the envelope in some way.”

For information about, and tickets to, “Toni Stone,” call 212-719-1300, or visit roundabouttheatre.org. Ticket prices range from $79 to $89.

Tinky Weisblat is the award-winning author of “The Pudding Hollow Cookbook,” “Pulling Taffy,” and “Love, Laughter, and Rhubarb.” Visit her website, www.TinkyCooks.com.