Naomi Osaka, Sloane Stephens talk mental health struggles after US Open losses

Two of tennis' biggest stars are opening up about their emotional struggles in the wake of their losses at this year's U.S. Open.

American tennis player Sloane Stephens gave a glimpse into the more than 2,000 abusive and hateful messages she said she received on social media following her third-round loss Friday to Angelique Kerber, ranked No. 17 in the world.

"I am human," Stephens, 28, wrote on Instagram Saturday. "It's so hard to read messages like these, but I'll post a few so you guys can see what it's like after a loss."

Stephens, a former U.S. Open champion now ranked 66th on the Women's Tennis Association (WTA) tour, shared screengrabs of the messages, some of which contained racist language, while others threatened physical and sexual violence.

"This type of hate is so exhausting and never-ending," she wrote. "This isn't talked about enough."

Prior to the U.S. Open, Stephens told "Good Morning America" she has learned over her decade-long professional tennis career to not keep her mental health struggles to herself.

"I feel like a lot of people try to fight it alone and end up in a deeper rut than they were in before because they didn't ask for help, or they didn't tell anyone or they didn't even say it out loud." Stephens said. "I wouldn't wish that. I've been in a place where it's been dark. And it's been deep, and it's been sad. And I'm like, I need to get out of that place."

On Friday, the same day Stephens lost her match, four-time Grand Slam singles champion Naomi Osaka was also knocked out of the U.S. Open early, losing in three sets to Leylah Fernandez, an unseeded 18-year-old from Canada.

After the loss, Osaka, 23, said she plans to take an indefinite break from tennis.

"Recently, like when I win, I don't feel happy. I feel more like a relief. And then when I lose, I feel very sad," Osaka said in press conference following her loss. "I don't think that's normal."

Osaka then began to cry, but said she wanted to continue instead of ending the press conference.

"Basically I feel like I'm kind of at this point where I'm trying to figure out what I want to do, and I honestly don't know when I'm going to play my next tennis match," she said. "I think I'm going to take a break from playing for a while."

The U.S. Open was the first Grand Slam tournament for Osaka this year after she bowed out of the French Open and Wimbledon due to what she said were mental health struggles.

Osaka withdrew from the French Open in June after being penalized for not doing post-match press conferences, which she said at the beginning of the tournament she would not do to preserve her mental health.

"I've often felt that people have no regard for athletes' mental health and this rings true whenever I see a press conference or partake in one," Osaka said in a statement she shared on social media prior to the French Open.

A few weeks later, the tennis superstar also decided not to compete in Wimbledon.

Osaka returned to play in the 2020 Tokyo Olympics in August in her home country but suffered a surprising loss in the third round.

Mental health experts have applauded Osaka for speaking up about her mental health, particularly as a woman and a woman of color.

"It does open up a conversation because it's her using her voice and her platform to really call out systemic change, which she has done before," Vaile Wright, Ph.D., a clinical psychologist and American Psychological Association's senior director of health care innovation, told "GMA" earlier this year. "I think she can show other girls and women who look like her how to empower them to stand up for themselves in ways that I think we haven't always been able to see."

The revelations from Osaka and Stephens about their mental health struggles as athletes in the spotlight come just a few weeks after American gymnastics star Simone Biles set aside her Olympic dreams to preserve her mental health.

Biles, 24, withdrew from several competitions at the Tokyo Olympics to "focus on her mental health," USA Gymnastics said at the time.

"It's been really stressful this Olympic Games, just as a whole," Biles said after her withdrawals were announced. "It's been a long week. It's been a long Olympic process. It's been a long year."

ABC News contributor and USA Today columnist Christine Brennan said it's "about time" when it comes to young athletes like Biles, Osaka and Stephen feeling empowered to talk openly about their mental health.

"What a monumental couple of months this has been ... for all young athletes and for all of us who watch and cheer for young athletes, especially women, especially women of color," Brennan said Monday on "GMA." "This is such an important time to be discussing these issues."

She called those speaking out "wonderful role models."

"They're still in their 20s. They're still very young. For them to have the courage and the will to bring this up and to fight this and to talk about it, I think is so admirable," she said.