Key moments from the Olympic Games: Day 5

Each day, ABC News will give you a roundup of key Olympic moments from the day’s events in Tokyo, happening 13 hours ahead of U.S. Eastern Time. After a 12-month delay, the unprecedented 2020 Summer Olympics is taking place without fans or spectators and under a state of emergency due to the coronavirus pandemic.

Simone Biles withdraws from individual all-around

American gymnastics superstar Simone Biles has decided not to compete in Thursday's final individual all-around competition at the Tokyo Olympics so that she can "focus on her mental health," USA Gymnastics said in a statement Wednesday.

"Simone will continue to be evaluated daily to determine whether or not to participate in next week’s individual event finals," the sport's national governing body added. "We wholeheartedly support Simone’s decision and applaud her bravery in prioritizing her well-being. Her courage shows, yet again, why she is a role model for so many."

Jade Carey, who had the ninth-highest score in qualifications, will compete in Biles' place in the all-around, according to USA Gymnastics. The decision follows Biles' early exit from the team final on Tuesday.

Katie Ledecky takes gold in 1st-ever women’s 1500 freestyle

Only an hour after she failed to place in the 200-meter freestyle, Team USA's swimming star Katie Ledecky was back in the pool racing for gold and Olympic history.

Ledecky easily beat her competition, winning by more than four seconds in the 30 lap-race and becoming the first woman to win a gold medal in a 1,500-meter freestyle. Her teammate Erica Sullivan won silver.

Athletes grapple with heat and humidity as Tropical Storm Nepartak makes landfall

The suffocating heat wave in Tokyo was so unbearable during the men's tennis singles final that Russian player Daniil Medvedev reportedly told the umpire: "I can finish the match, but I can die ... If I die, are you going to be responsible?"

Temperatures in the Olympic host city were at around 88 degrees Fahrenheit, but the humidity from recent rain showers moved the heat index up to 99.

Tropical Storm Nepartak ultimately spared the Games and made landfall on Wednesday morning in Japan's Miyagi prefecture, some 250 miles north of Tokyo.

COVID-19 cases at Tokyo Olympics rise to 174

There were 14 newly confirmed cases of COVID-19 among people at the Tokyo Olympics on Wednesday, including contractors, media members and Games-concerned personnel. The total now stands at 174, according to data released by the Tokyo 2020 organizing committee.

The surrounding city of Tokyo reported 3,177 new cases on Wednesday, a 7-day average increase of 153%, according to data released by the Tokyo metropolitan government.

U.S. men's basketball team bounces back from 1st round loss to defeat Iran

After losing their first game since 2004 on Sunday to France, the U.S. men's basketball team easily beat Iran 120-66. Players Damian Lillard and Devin Booker helped lead Team USA to victory with 21 and 16 points, respectively.

Team USA has one more game in the group round on Saturday against Czech Republic.

Novak Djokovic keeps Golden Slam dream alive

Serbian tennis player Novak Djokovic defeated Spain's Alejandro Davidovich Fokina 6-3, 6-1 in the third round match of the men's singles.

Djokovic is now three matches away from achieving a Golden Slam, which is when a tennis player wins all four Grand Slam tournaments as well as a gold medal at the Summer Olympics in a single calendar year. Steffi Graf of Germany is the only player to accomplish such a feat.

U.S. women’s 3x3 basketball wins gold in inaugural year

The U.S. women’s team beat Team ROC 18-15 to win the first-ever gold medal in women’s 3x3 basketball. The U.S. team only lost one game throughout the entire tournament, and the win increases Team USA’s gold medal count to 11.

More scenes from today's action:

Catch up on the best moments from the previous days' events

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