NEW YORK — The New York Mets are deep in a season that defies adjectives. Puzzling? Disappointing? Maddening? All apply, which is why Marysol Castro considers herself a voice of hope. Or maybe a voice of reason.

Hers is one of those voices you don’t realize you’re hearing when you hear it, like the one that says “This is ‘NBC Nightly News’ with Lester Holt.” Her audience is averaging about 29,000, triple what it would be if she did the same job in Miami, about a third less than if she did it in St. Louis.

She is a public-address announcer for the New York Mets.

Castro, 44, is in her first season at Citi Field. She is all too aware of how fleeting first place can be — or, for the Mets, was. She has lived through the heartbreaking purgatory of last place, the recent climb into fourth in the National League East and, just when you figured all the adjectives had been exhausted, the anomalous August.

“Those first 11 games were great,” she said, referring to the Mets’ 11 wins in their first 12 games. “Then the rest happened. I still have to show up and be the voice, right?”

It is a voice that die-hard Mets noticed from, well, Day 2. “I thought: “Oh, cool, a female PA announcer,” @BryanUF wrote on Twitter on June 1. “I had no idea that was only the second day on the job for @marysolcastro, the first female PA announcer for the Mets. Congrats on making history!” She is also the first Latina announcer in Major League Baseball.

It is probably best not to tell the Mets crowd that Castro grew up in the shadow of a certain stadium in the Bronx that is home to a certain American League team. “In the early ’80s, it was all Yankees all the time,” she said, “but obviously in 1986, when I was in sixth grade, everybody loved the Mets. Ron Darling, he’s so cute. Keith Hernandez, he’s so hot, he’s so great. Now I pass those guys in the hallway.”

So she has converted to the peculiar denomination that is the Mets. Her job is not just about saying the words — lines like “Here is your lineup for your New York Mets” never change — it is about finding the tone that sets, or captures, the mood in the stadium. She said she told the team’s producers when she auditioned, “I don’t want to sound too rah-rah-rah.” She said that would sound “inauthentic.”

Still, she sounds a certain way when she is introducing Mets players, and it is different from the way she sounds when she is announcing the other team’s players. She smiles when she announces the Mets. “That allows me to sound warmer,” she said. “When I’m using my visitors’ voice, I’m not smiling.”

And there are times when she tries to fire up the crowd by giving the next batter’s name a little extra oomph.

But we are talking about the Mets. “When you’re down by a ton, I’m not getting into that rah-rah voice,” she said. “I’m getting into, it’s serious but we’re still in this. ‘No. 9, Brandon Nimmo.’”

The Mets know all about being down by a ton. This is the team that was obliterated by the Washington Nationals 25-4 on July 31, the worst loss in Mets history. The Mets also know about being up by a ton, as when they beat the Baltimore Orioles 16-5 on Wednesday and the Philadelphia Phillies 24-4 on Thursday, becoming the first National League team to score at least 15 times in back-to-back games since 1933, according to the Elias Sports Bureau.

Castro did not have to deal with any of the lopsidedness. The big loss and the big wins came in away games.

Still, she said, “I would have loved to announce Jose Reyes as a pitcher” in the Washington game. Reyes, an infielder who was an entertaining and energetic shortstop when he was younger, was sent in to pitch the eighth inning. The Nationals scored their last six runs off him, including two homers.

Castro had been an English teacher at Poly Prep Country Day School in Brooklyn, and a television reporter before the Mets hired her. She had worked for ABC News, WPIX-TV and ESPN, among other outlets. (She is one of two public-address announcers the Mets hired in the spring. The other is Colin Cosell, the grandson of bombastic sports broadcaster Howard Cosell.)

But being a voice of the Mets is different from working as a television reporter. “I don’t have to have my hair and makeup done, which is great,” she said.

Her usual game-day outfit is “ripped jeans and a T-shirt, and my hair is in a ponytail,” she said. “It is highly plausible to show up in sweatpants, but you never know when the Wilpons will show up.” (The Wilpon family owns the Mets.)

On game days, she arrives a couple of hours before the first pitch and goes over the lineups. During games, “I have trained myself to watch the specific spot where Mickey stands,” she said, referring to the manager, Mickey Callaway.

“If he’s putting both of his hands over his ears, he’s going to question the play,” she said. “Or if he steps out of the dugout, does he have a piece of paper in his hands, because if he does, the double switch is coming. We wait. It’s not like someone’s calling us and saying, ‘Hey, guys it’s going to happen.’” She has help from a spotter in the announcer’s booth.

She was hired after two auditions. At the first, she asked, “What kind of voice do you want? What kind of delivery do you want?”

“I said, ‘I’ve got a lot of different registers, tell me what you want,’” she recalled. “They said, ‘Your speaking voice on the phone is great. If you can pronounce the Latino names in Spanish, that would be great.’ I said, ‘OK, perfect.’”

The second audition was at Citi Field, using the public-address system.

“I said, ‘OK, you’ve heard my voice, because I’ve done “New Year’s Rockin’ Eve” with 3 million of my best friends around me, and I’ve flown down to cover hurricanes while they’re coming ashore.’ I said, ‘I’ve got my furniture-selling voice, I’ve got my Marysol voice, you tell me.’ They said, ‘We like the Marysol voice.’”

So she introduced Asdrubal Cabrera, the infielder whom the Mets traded to the Phillies last month, with a Spanish pronunciation. “No one had ever heard it come out of the loudspeaker like that. The radio guys would say, ‘Never heard it like that before, but we guess that’s how it’s pronounced.’” She also introduced Adrian Gonzalez, the first baseman whom the Mets released last month, after checking with him. “He said, ‘Yeah, that would be really cool, folks in Mexico would be happy.’”

The reaction at home, when Castro told her two sons that she was taking the job, was less enthusiastic.

“The 9-year-old went, ‘Really, it couldn’t be the Yankees?’” she recalled.

Her 12-year-old said, “There aren’t many women who have that job.” “He went to the computer and he said, ‘You’re the second woman to do this. Holy smokes.’ (Sherry Davis was the first full-time female public-address announcer in the majors, for the San Francisco Giants from 1993 to 1999.) Then he said, ‘Is it taco Tuesday? Because I’m hungry.’”