Olympic Coach Who Saved Swimmer Recounts 'Nightmare' Accident: 'She Was Not Breathing'

When Andrea Fuentes jumped into the water to save Anita Alvarez, her "only goal was to fix it," the U.S. swimming coach tells PEOPLE.

Fuentes, 39, dramatically rescued Alvarez, 25, who was sinking to the bottom of the pool after passing out at the end of her routine. Initially, Fuentes "didn't think she was going to pass out at all," despite noticing that Alvarez's "feet were a little bit more pale than usual."

"I thought that she was just doing a huge effort and I was proud of her because that's the world champs, it's the final. So I was like, she's pushing through her limit as much as she can," said Fuentes, who called the experience a "difficult nightmare."

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It wasn't until Alvarez didn't come up for a breath after the routine that Fuentes knew something was wrong. "I realized that she was not okay because in our sport, it's really important to breathe when you finish. So as soon as she went down, I immediately recognized that she passed out," said Fuentes. "I know her very well, I see her a lot of hours every day," she said.

OLI SCARFF/AFP via Getty Images Coach Andrea Fuentes (R) rescuing swimmer Anita Alvarez

"My thought at that moment is, okay, I have to take her out. Because I don't know, I was not expecting nobody to go," she recalled. Fuentes told PEOPLE she "feels that responsibility," with her swimmers. "I didn't even think [if] I have to go or not, I just went," she said. "So, I just went as fast as I could and it was I think the longest 25 meters of my life."

The retired Olympic swimmer recalled feeling the weight of her clothes in the water, including a "polo, which is much heavier." What's more, the pool was 10-feet-deep. "When I arrived to her, she was touching the bottom already. So I used the bottom to go up," Fuentes said.

PETER KOHALMI/AFP via Getty Images Coach Andrea Fuentes (L) rescuing swimmer Anita Alvarez

"We reached the surface and I noticed that [Alvarez] was not breathing," says Fuentes, who didn't freak out in the "really scary" moment. "I just said, 'Do whatever it takes to make her breathe.' So my only goal was fix it."

Eventually, Fuentes had to resort to an "extremely painful" method to help Alvarez regain consciousness, a slap. "You have to do whatever it takes for her to react," said Fuentes. "And so I moved her very strongly for her to wake up, but she was still not." But when the slap didn't work, she remembered a more extreme strategy.

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OLI SCARFF/AFP/Getty Coach Andrea Fuentes (R) rescuing swimmer Anita Alvarez

Unsure what the method is referred to in English, Fuentes explained, "You press the pinky nail, very, very strong with something hard and this is extremely painful."

According to Fuentes, this method is used "when somebody's gone." She continued, "If this doesn't wake the person up, then you have a big problem. But in this case, it's so painful that the body creates a lot of adrenaline and wakes you up."

Thanks to Fuentes, the nail method was successful and Alvarez regained consciousness immediately after. Fuentes recalled, "[Alvarez] woke up suddenly yelling at us, like, 'What are you…' And I was okay because thank God she's okay. And then she just cough completely everything and start breathing."

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OLI SCARFF/AFP via Getty Images Coach Andrea Fuentes (R) rescuing swimmer Anita Alvarez

Now, Fuentes encourages everyone to be aware of water safety, whether they're in the pool or the ocean this summer.

"I feel a little bit like I have the role now to create the awareness of that because we are professionals and it's our job," said Fuentes, who believes water safety should be taught in schools. "I think that's something that they should teach at school to everybody, this lesson should be at every school."