Simone Biles sent shockwaves through the Summer Games on Tuesday when she dropped out of the team competition on her opening vault after receiving a low mark.
The 24-year-old said the pressure of living up to expectations and her quest for a record gold medal haul had left her no choice but to drop out for her own mental health. She did not rule out a return to competition starting with Thursday's all-around event, where she would defend her Olympic title.
"We have to protect our mind and our body rather than just go out there and do what the world wants us to do," Biles told reporters.
"We're going to see about Thursday. We're going to take it a day at a time."
Her withdrawal from the team event came hours after tennis superstar Naomi Osaka lost in her Olympic singles event on Tuesday, her first tournament since pulling out of the French Open in May, when she said she had been suffering from depression for nearly three years.
"More could be done" on athlete mental health, the spokesman for the International Olympic Commission Mark Adams told reporters on Wednesday.
He said mental health remained a big issue and that it was a matter the organisation had been working on for some time.
In the pool on Wednesday, women once again stole the show. Ariarne Titmus won a second gold medal in Tokyo, her first Olympics. Dubbed the "Terminator", she accelerated in the final metres to finish ahead of Ledecky, whom she beat for a second time after winning the 400m freestyle on Monday.
"I'm just from a small town in Tasmania and it just goes to show if you believe you can do something, you can 100% do it if you work for it," Titmus told Australia's ABC News.
American Ledecky took gold in the 1500m freestyle, the first time the event has been held for women. Diversity is a focus for the Tokyo Olympics with women's events being added in other sports, including boxing.
Titmus and Ledecky are expected to face each other again in the 800m freestyle on Saturday, in which the American is heavily favoured, and they will also be on opposite sides in the 4x200m relay.
Swimmer Yui Ohashi also took her second gold medal in the 200m medley after victory in the 400m medley on Sunday.
She pipped American Alex Walsh in the final, freestyle leg of the race to the delight of her Japanese team mates in the spectator-free arena.
"Seems like a dream," said Ohashi. "It doesn’t feel real. In the last 15 it was really hard, my legs were really hurting but I just kept kicking."
Japan's baseball team warmed up early Wednesday under a partly cloudy sky in disaster-struck Fukushima ahead of a game with the Dominican Republic to open the six-team competition in the sport.
The pandemic has continued to hang over the Olympics, particularly after the host city announced a record number of daily COVID-19 cases on Tuesday.
Though Japanese Prime Minister Yoshihide Suga shut down any possibility of cancelling the Olympics late on Tuesday, organisers are likely to remain on high alert for any major breach of its bubble, where athletes and others involved in the Games avoid any public contact.
Organisers have so far reported 169 COVID-19 cases related to the Games, a miniscule number given the tens of thousands of people visiting for the event.
Three prefectures near the host city - Chiba, Kanagawa and Saitama - are set to ask the government to declare states of emergency for their regions, a minister said.
(Reporting by Simon Evens, Steve Keating; Additional reporting by Reuters Olympics team; Writing by David Dolan; Editing by Stephen Coates, Michael Perry & Shri Navaratnam) ((firstname.lastname@example.org; +81 3 4563 2749;))