SAN FRANCISCO >> Since the Giants opened a state-of-the-art waterfront ballpark in 2000, the franchise has cycled through three managers, four stadium names and several hundred players.

There’s been just one public-address announcer. Renel Brooks-Moon has introduced every one of those players.

“First of all, my mind is still blown that I’m here two decades,” Brooks-Moon said.

As the first and only female African-American public address announcer in Major League Baseball — and still just one of two women stadium announcers in MLB — Brooks-Moon is revered as a trailblazer. Now she’s leading other women on the trail.

“Renel doesn’t even know how much she has impacted not just women breaking down barriers, but any sort of minority in this field,” Giants’ in-game host Therese Viñal said. “She has been a light and a loudspeaker.”

Twenty years after she first spoke into the microphone at what was then known as Pac Bell Park, Brooks-Moon is at the center of an ever-growing circle of women in on-air roles with the Giants. Amy Gutierrez is the field reporter for NBC Sports Bay Area. Kelli Johnson hosts the pregame and postgame shows for NBCSBA. Carmen Kiew co-hosts her own postgame show, “Triples Alley,” on NBCSBA. Viñal makes five.

“When you’re given the privilege of these opportunities, you must make sure that you are the first, but you are not the last,” Brooks-Moon said. “That’s how I was raised. It’s personal for me and I really feel blessed that I am in this position to be able to have some sort of impact. To be a shoulder, an ear, whatever you need. Because I had nobody.”

Brooks-Moon is not the first female public address announcer in Giants history. That honor belonged to Sherry Davis, who welcomed fans to Candlestick Park from 1993-99. Like Davis, Brooks-Moon was initially the only female voice to be heard from the ballpark. That changed in 2008 when Gutierrez moved from a role as a producer to an on-camera TV reporter.

“Renel is one of my biggest mentors,” Gutierrez said. “Not only did I grow up listening to her on the radio, I already knew who she was, I got a chance to produce her and she was my talent for GMag. She was this trailblazer for all of us.”

A Petaluma, California native and 1995 graduate of UC Davis, Gutierrez said she might not have continued beyond her first year if not for the unyielding support of Giants broadcasters Mike Krukow and Duane Kuiper.

“They pulled me aside and said, ‘You’re good, we’ve got you.’” Gutierrez said. “And I needed that because the first few years weren’t great.”

Johnson starred as a college basketball player at the University of Idaho from 1994-1997 before embarking on a career as an on-camera sports reporter and digital beat reporter in stops that included Medford, Oregon, St. Louis, Missouri and Washington, D.C. She arrived at NBC Sports Bay Area in 2014 and took over as the Giants’ pre and postgame show host this year following Ahmed Fareed’s departure.

“I tried to find my own way and I’m very much an old-school baseball type,” said Johnson, the daughter of a baseball coach. “Ahmed is new school, he’s into the analytics, he’s a baseball nerd while I’m still trying to learn all of that stuff. I’ve always been into stats and numbers, but this new level of numbers is crazy and it can be overwhelming. Not to mention, it can put fans to sleep because they’re like, ‘What did you just tell me?”

Kiew is also new to NBC Sports Bay Area’s Giants coverage this season as she was hired to join Viñal as one of the co-hosts on “Triples Alley.” the network’s second postgame show.

Kiew’s father Kelvin raised her as a diehard baseball fan and she played four years of softball at Lynbrook High in San Jose, but even after graduating from Pitzer College in 2005, Kiew said she had no plans to pursue a career in sports media.

“I don’t think I ever thought I could do this as a living,” Kiew said. “Whether it be I didn’t see a lot of women doing it or the fact I just think I personally couldn’t do it, monetize it and make it into a career, I just think that was a barrier in my mind subconsciously.”

Viñal ran into barriers after her career had begun, but she was initially influenced to pursue a job in sports media after listening to a particularly captivating speaker at career day when she was a three-sport athlete at Presentation High in San Jose.

“After Renel came and spoke, I went home and said, ‘Mom, I know what I want to do with my life. I want to talk about sports.’” said Viñal, who played volleyball and majored in broadcast journalism at CU-Boulder from 2004-2007.

After leaving her job as a multimedia sports reporter at a TV station in Toledo, Ohio and believing her on-camera career was finished, Viñal was skeptical of applying with the Giants. She did anyway prior to the 2015 season as a favor to one of her bosses in the digital department at what’s now NBC Sports Bay Area.

Five years after leaving a full-time job for a brand new part-time position, Viñal might be the busiest person in Bay Area sports media.

Viñal’s weekday commutes from her home in Pebble Beach begin as early as 9:30 a.m. for a 6:45 p.m. game. If the Giants play for three hours, “Triples Alley” won’t hit the airwaves until roughly 11:30 p.m.

“When there’s times that I wonder if I can still keep doing this as a mom and dealing with a commute and dealing with some of the stuff that you do on social media, you start to doubt yourself,” Viñal said. “I just remind myself of how long Renel has been doing this and what she has endured. The same goes for Amy G. I see the two of them and how they have just powered through and paved the way.”

Far too often, the criticism the women in on-air roles face comes from anonymous social media accounts or men seeking to challenge their credentials. Three of the women covering the Giants — Johnson, Gutierrez and Vinal — played Division I college sports while two others — Brooks-Moon and Kiew — developed a passion for the game at an early age.

“It would be really nice if we had a world where if that’s what she wants to do, then she would have the opportunity to do it,” Gutierrez said. “We didn’t have to go up against a social conscience that says that doesn’t sound right or that doesn’t look right. If we can get rid of that and go with, who’s the best at it? Who’s the most qualified? Who’s put in the time and who’s done the journey?”

Criticism is a constant, but all of the women who have followed Brooks-Moon and covered the Giants from what is now Oracle Park acknowledge that her leadership and the grace with which she has handled her responsibilities has inspired them to see beyond what’s said on social media.

Brooks-Moon takes an immense sense of pride in the community she’s helped nurture inside a ballpark celebrating its 20th year of operation, particularly because she was raised to lead.

Brooks-Moon’s father, Nathaniel Hawthorne Brooks, Sr., was the first African-American high school principal in San Francisco when he was hired at Polytechnic High in 1968, 10 years after his daughter was born. Through her father’s experience, Brooks-Moon said she learned that “to whom much is given, much is required.”

She said many of the hurdles that existed for her in 2000 are still present for other women today, but there’s now a much larger group of dedicated role models motivated to help the next generation. One of the most important lessons she’s attempted to impart on women in sports media is that while the industry is competitive and there may seem like only a small number of opportunities exist, there’s room for growth and always room for more women.

“We have enough to fight against, especially in this industry, we cannot fight against each other,” Brooks-Moon said. “There’s room for all of us and we’re like the Warriors, strength in numbers.”

That concept of strength in numbers has led to strength in possibilities.

“I hope that girls growing up know that there are no limitations to anything they want to do,” Johnson said. “If they want to be in sports broadcast or if they want to be the president of the United States, they can do it. You put in the work, the effort, you have the right attitude, you have the work ethic and the belief and confidence in yourself, there just aren’t any limits.”

Several of the women we spoke with including Kiew, who also co-hosts KNBR’s Talkin’ Baseball with Marty Lurie, noted the disparity in on-air radio hosts in the Bay Area. Bonnie-Jill Laflin is the only co-host of any weekday show host in KNBR’s lineup while Anna Kagarakis is the only co-host currently featured on a weekday show on 95.7 The Game.

“Honestly the on-air situations here are not great for females,” Kiew said. “There’s barely any representation for females, women of color, people of color. There needs to be more diversity. Because we’re hearing the same opinions recycled over and over again. People are getting bored around the game and maybe it’s because the content around the game is repetitive.”

Two of the key frontiers for progress remain the broadcast booth and the front office, where only a handful of women have received opportunities across professional baseball. Like Brooks-Moon in San Francisco, pioneers like New York Yankees assistant general manager Jean Afterman and ESPN Sunday Night Baseball color commentator Jessica Mendoza have played foundational roles in showing women what’s possible in the sport.

With more glass ceilings left to shatter, the women covering the San Francisco Giants are determined to see more progress come to fruition.

It took too long for many changes to take place, but after 20 years in the public address announcer’s booth, it’s a thrill for Brooks-Moon to sit back and realize what she has helped accomplish.

“Change is difficult when you’re trying to make an impact on something that has traditionally been so male-dominated,” Brooks-Moon. “There of course are going to be haters, there of course are going to be roadblocks, but I could not be more thrilled to have more estrogen around here.”