The first pitch of Friday night’s Sonoma Stompers baseball game was a breaking ball that went over the plate and into professional baseball history.

The pitch itself wasn’t that special, but the called strike was thrown by a woman, one of two who started the game for the Stompers against the San Rafael Pacifics at Arnold Field in Sonoma. It is believed to be the first time in more than 60 years that a team with more than one woman has participated in a professional baseball game.



Stacy Piagno, the 25-year-old pitcher from St. Augustine, Fla., made it through the first inning, gave up two runs in the second and lasted until the third inning. Behind her, in left field, was Kelsie Whitmore, 17, of Temecula (Riverside County), who tracked down a deep fly ball near the left field fence to end the first inning. Stompers officials consider Whitmore the best female baseball player in the country.

“It’s exciting. I’ve got goosebumps,” said Lizette Dalquie, 64, of Sonoma, as she sat in the stands waiting for the first two female ballplayers in the four-team independent Pacific Association baseball league to take the field. “It’s a breakthrough for the girls.”

It was a big deal for what most people would consider small-town baseball. Piagno and Whitmore received by far the biggest ovations in the sold-out ballpark, which was bustling with more than 700 people, not including the jostling reporters and photographers.

It was clear from the start that most of the crowd had come for the gender equity aspect of things.

“I played Little League with the boys growing up and my first year I got hit by a pitch every single game, but I kept on playing,” said Amber Williams, 36, a fifth-grade teacher in Sonoma, who said she came to the game with her 4-year-old daughter, her sister-in-law and two nieces just to see the women play. “This means that the kind of discrimination I grew up with is changing, and that anything is possible for a girl these days.”

Lenin Salinas, 27, drove all the way from San Francisco to see what he called a historic game.

“I’m a baseball coach for both boys and girls, and it’s great to see girls being competitive,” Salinas said. “It’s a win for equality. It’s a win for everybody.”

The two women may have made a statement for their sex, but their performances probably won’t have many big-league scouts knocking on their doors. Piagno gave up three hits, including two RBI doubles, and walked two. Two errors were also committed behind her. Whitmore walked and struck out in two plate appearances. The Stompers ultimately lost 8-4.

Both women said they were happy with their performances and hope to continue improving.

“My goal is really just to become a better athlete, to become smarter, stronger, both mentally and physically,” Piagno said. “Yes, me and Kelsie are paving the way for young girls, which is amazing and it’s great, but at the same time we are doing this because this is a game that we love.”

The important thing, said Stompers General Manager Theo Fightmaster, is that the girls fit right in.

“They’re ballplayers,” Fightmaster said, adding that they will have to earn their places on the team this summer.

The bright idea to recruit women was first floated by none other than film director Francis Ford Coppola, who said in a news release that he always wondered why there weren’t co-ed teams in professional baseball, given that the game doesn’t rely as much on size and strength as other sports.

“My family would play co-ed baseball games and inevitably the star player would always be an aunt,” said Coppola, whose Virginia Dare Winery in Geyserville has been a primary sponsor of the team over the past three years. “So when my Sonoma winery became involved with the Stompers, I had the opportunity to turn this thought into a reality and recruit these amazing women capable of playing alongside men.”

Team officials scouted Piagno and Whitmore at the tryouts for Team USA, which is scheduled to play in the Women’s Baseball World Cup in South Korea this fall. They both came in with sterling credentials.

Piagno no-hit Puerto Rico while playing for the gold-medal-winning United States team at the 2015 Pan Am Games in Toronto. She was a star softball player at the University of Tampa. Whitmore, who recently graduated from Temecula Valley High School, will attend Cal State Fullerton on a softball scholarship this coming year, though she has played softball only once before, in a tournament.

Both women played baseball against boys in high school.

“People have come up to me and thanked me, and I think I can be a role model for some people, younger girls that look up to me,” Whitmore said. “I never really had a role model — older baseball players that were girls to look up to — so I think I can be one to other people.”

Fightmaster said they are among a half dozen female baseball players the team has scouted across the country.

Top Stompers brass denied the new signings were a publicity stunt, but they nevertheless took full advantage of the jostling cameras, which couldn’t help but notice the crowd-pleasing antics of Rawhide, the team’s bull-like mascot. He shimmied to television jingles and “YMCA,” by the Village People, which served as the between-innings dance piece de resistance.

It isn’t the first time women have played baseball with or against men. The most famous battle of the sexes occurred in the mid-1990s when Hall of Fame knuckleball pitcher Phil Niekro recruited the best female ballplayers in the country to play as the Colorado Silver Bullets.

The team, which was made up mostly of top college softball players, went up against minor-league and college teams at first, taking several severe shellackings before lowering expectations. Later, they competed against men’s amateur and semipro teams, including U.S. Navy and Hollywood stars teams. In 1997, the Bullets’ last year, they won 23 games and lost 22, their first winning season.

More recently, Ila Borders and Eri Yoshida have pitched for professional baseball teams. The Stompers, however, are believed to be the first professional team with more than one woman since the 1950s, when Toni Stone, Mamie “Peanut” Johnson and Constance Morgan played in the Negro Leagues.

The Stompers have, in fact, been unusually progressive since the team was founded in 2014. Stompers pitcher Sean Conroy became the first openly gay professional baseball player in 2015. He threw a complete game shutout in his first start, Pride Night, and his teammates wore rainbow socks.

After all, Fightmaster said, if baseball is going to continue to be the national pastime, it should reflect America.

“There are girls that love this game, too,” Fightmaster said, “They should be able to play.”

Peter Fimrite is a San Francisco Chronicle staff writer. Email: pfimrite@sfchronicle.com Twitter: @pfimrite