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.
Sydney McLaughlin wins gold, sets a new world record in 400m hurdles
Team USA's Sydney McLaughlin set a new world record of 51.46 seconds for the 400m hurdles and picked up the gold medal along the way. She was congratulated by teammate Dalilah Muhammad who won the silver in the event.
The previous world record for the men's 400m hurdles was also smashed yesterday by Norway's Karsten Warholm.
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Sydney McLaughlin of Team United States competes in the Women's 400m Hurdles Final on day twelve of the Tokyo 2020 Olympic Games at Olympic Stadium on Aug. 04, 2021 in Tokyo, Japan.
Eduardo Munoz Alvarez/AP Photo
People celebrate during a watch party Tuesday, Aug. 3, 2021, in Mountainside, N.J., the gold medal of Sydney McLaughlin in the women's 400-meter hurdles at the 2020 Tokyo Olympics.
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Gold medalist Sydney McLaughlin of Team United States poses in front of the scoreboard after setting a new world record in the Women's 400m Hurdles Final on day twelve of the Tokyo 2020 Olympic Games at Olympic Stadium on Aug. 04, 2021 in Tokyo, Japan.
U.S. women’s basketball heads to semifinals, win streak extended to 53
The United States women’s basketball team has now won 53 straight games at the Olympics, a streak extending from the 1992 Olympic Games. Team USA defeated Australia 79-55 in an effort led by Breanna Stewart with 23 points.
JOE GIDDENS/EPA-EFE/Shutterstock
Breanna Stewart of the USA competes for the ball with Alanna Smith of Australia during the Women's Quarterfinal Basketball match during the Tokyo Olympic Games in Saitama, Japan, Aug. 4, 2021.
USA baseball sets sights on gold after 3-1 win over Dominica
The U.S. baseball team beat the Dominican Republic 3-1 to stay in the hunt for gold. Triston Casas hit his third home run of the Olympic Games and Team USA will play the loser of Japan-South Korea next on Thursday.
Sue Ogrocki/AP Photo
United States' Tyler Austin celebrates his home run with teammate Todd Frazier (25) in the fifth inning of a baseball game against the Dominican Republic at the 2020 Summer Olympics, Aug. 4, 2021, in Yokohama, Japan.
COVID-19 cases at Tokyo Olympics rise to 327
There were 28 newly confirmed cases of COVID-19 at the Tokyo Olympics on Wednesday, including four athletes, three of whom were staying at the Olympic Village at the time of the positive test. The Greek artistic swimming team was hit the hardest and was ruled out after 5 of the 12 athletes or team officials tested positive. The total now stands at 327, according to data released by the Tokyo 2020 organizing committee.
The surrounding city of Tokyo reported 4,166 new cases on Wednesday, a seven-day average increase of 178.0%, according to data from the Tokyo metropolitan government.
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Rows of empty seats are seen in the Olympic Stadium as the Athletics continues on day 12 of the Tokyo Olympic Games on August 4, 2021 in Tokyo, Japan.
Allyson Felix one step closer to making history
U.S. sprinter Allyson Felix finished second in her heat and advanced to the finals of the women's 400m, putting her one step closer to reaching a record 10 Olympic medals.
If Felix medals in the 400m, she would have the record for most medals of any female track and field athlete with 10. If she also wins a medal in the 4x400m relay, she would surpass legend Carl Lewis with the most track and field medals ever. The Tokyo Games are the fifth Olympics for the 35-year-old track star.
MORE: How Allyson Felix could make history at the Tokyo Olympics
Aleksandra Szmigiel/Reuters
Allyson Felix of the United States is seen before competing in the women's 400m on Aug. 4, 2021 in Tokyo, Japan.
Japan extends domination in skateboarding events
Japan's Sakura Yosozumi won the gold in the first ever Olympic skateboarding park event, followed by 12-year-old Kokona Hiraki, Japan's youngest medalist.
Ben Curtis/AP Photo
Sakura Yosozumi of Japan competes in the women's park skateboarding finals at the 2020 Summer Olympics, Aug. 4, 2021, in Tokyo, Japan.
Belarusian sprinter Krystsina Tsimanouskaya leaves Tokyo for Vienna
Krystsina Tsimanouskaya left Tokyo for Vienna, Austria, after spending the last two nights at the Polish embassy where she was granted a humanitarian visa.
Tsimanouskaya said she was excluded from her events and hustled to an out-bound flight by her Belarusian Olympic committee after she criticized them on social media. The Associated Press reported that Belarusian Olympic officials hinted she would face punishment upon her return home.
Tsimanouskaya never boarded the Belarus-bound flight after she hailed airport police and was put under their protection at the Haneda airport.
MORE: EXPLAINER: What is behind Belarus athlete's Olympics crisis?
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Belarus athlete Krystsina Tsimanouskaya walks through Terminal 1 before boarding her Vienna-bound flight at Narita International Airport in Narita, Chiba Prefecture, outside Tokyo on Aug. 4, 2021, after travelling from the Polish embassy where she had spent the past two nights.
Tamyra Mensah-Stock makes history, has grand plans for cash prize
U.S. wrestler Tamyra Mensah-Stock won the gold medal in the women's freestyle 68kg competition yesterday, the first Black woman to ever win Olympic gold in wrestling. Mensah-Stock said she knows exactly what to do with the $37,500 prize she will receive for winning the gold.
“I wanted to give my mom $30,000 so she can get a food truck. It’s her dream,” Mensah-Stock said. “My mom’s getting her food truck! She can cook really, really, really well – barbecue.”
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Tamyra Mariama Mensah-Stock of Team United States celebrates defeating Blessing Oborududu of Team Nigeria during the Women's Freestyle 68kg Gold Medal Match on day eleven of the Tokyo 2020 Olympic Games at Makuhari Messe Hall on Aug. 3, 2021 in Chiba, Japan.
Medal-worthy hair at the Tokyo Games
Gregory Bull/AP Photo
Uche Eke, of Nigeria, competes on the horizontal bar during the men's artistic gymnastic qualifications at the 2020 Summer Olympics, July 24, 2021, in Tokyo, Japan.
Kai Pfaffenbach/Reuters
Shelly-Ann Fraser-Pryce of Jamaica runs in the women's 200m semifinal on Aug. 2, 2021, in Tokyo, Japan.
Gregorio Borgia/AP Photo
Kiran Badloe, from the Netherlands, stands during competition in the windsurfing RS:X class at the 2020 Summer Olympics, July 24, 2021, in Fujisawa, Japan.
Patrick Semansky/AP Photo
Naomi Osaka, of Japan, serves to Viktorija Golubic, of Switzerland, during second round of the tennis competition at the 2020 Summer Olympics, July 26, 2021, in Tokyo, Japan.
Aleksandra Szmigiel/Reuters
Gabriela Debues-Stafford of Canada competes in the women's 1500m on Aug. 2, 2021, in Tokyo, Japan.
Alex Brandon/AP Photo
Mongolian coach Undralbat Lkhagva has the Olympic rings cut and dyed into his hair as he watches the women's 10-meter air pistol at the Asaka Shooting Range in the 2020 Summer Olympics, July 25, 2021, in Tokyo, Japan.
Kai Pfaffenbach/Reuters
Raven Saunders of the United States is seen in action in the women's shot put on Aug. 1, 2021 in Tokyo, Japan.
Shuji Kajiyama/AP Photo
Russian Olympic Committee's Alena Tiron's braids fly as she plays in their women's rugby sevens match against New Zealand at the 2020 Summer Olympics, July 30, 2021 in Tokyo, Japan.
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Stephanie Mawuli's hair is pictured in the 3x3 Basketball competition on day four of the Tokyo 2020 Olympic Games on July 27, 2021 in Tokyo, Japan.
Kazuhiro Nogi/AFP via Getty Images
Australia's Cameron Smith, with the letters AUS shaved into his hair, puts on his hat during round 4 of the mens golf individual stroke play during the Tokyo 2020 Olympic Games at the Kasumigaseki Country Club in Kawagoe on Aug. 1, 2021.
Hannah Mckay/Reuters
Tatjana Pinto of Germany is seen before competing in Heat 2 of the women's 100m on July 30, 2021, in Tokyo, Japan.
Kai Pfaffenbach/Reuters
Shaunae Miller-Uibo of the Bahamas runs in the women's 400m semifinal on Aug. 4, 2021, in Tokyo, Japan.
More scenes from today's Olympic action:
Olivier Morin/AFP via Getty Images
Japan's Ai Yoshida and Miho Yoshioka, Britain's Hannah Mills and Eilidh Mcintyre and France's Aloise Retornaz and Camille Lecointre sail past Mount Fuji during the women's two-person dinghy 470 medal race in Fujisawa, Japan, on Aug. 4, 2021.
Andrew Boyers/Reuters
Athletes compete in 110 hurdles on Aug. 4, 2021, in Tokyo, Japan.
Matthew Childs/Reuters
Cyclists from Team New Zealand are seen in action of the men's team pursuit on Aug. 4, 2021 in Shizuoka, Japan.
Pool via Reuters
Shauna Coxsey of Britain is seen in action during speed qualification on Aug. 4, 2021, in Tokyo, Japan.
Jung Yeon-je/AFP via Getty Images
China's Fan Zhendong competes against South Korea's Jang Woo-jin during their men's team semifinal table tennis match at the Tokyo Metropolitan Gymnasium during the Tokyo 2020 Olympic Games in Tokyo on Aug. 4, 2021.
Danny Lawson/PA Images via Getty Images
Great Britain's Jason Kenny is seen in the men's sprint qualifying at the Izu Velodrome on Aug. 4, 2021, in Shizuoka, Japan.
Andrew Boyers/Reuters
Genevieve Gregson of Australia reacts after falling down during the women's 3000m steeplechase on Aug. 4, 2021, in Tokyo, Japan.
Jewel Samad/AFP via Getty Images
Uganda's Peruth Chemutai reacts after winning the women's 3000m steeplechase final during the Tokyo 2020 Olympic Games at the Olympic Stadium in Tokyo on Aug. 4, 2021.
Catch up on the best moments from the previous days' events
MORE: Simone Biles finishes with bronze: Key moments from Day 11 of the Olympic Games
MORE: Key moments from the Olympic Games: Day 10
MORE: Key moments from the Olympic Games: Day 9
MORE: Tokyo Olympics opening ceremony: Best moments from the event
SLIDESHOW: Tokyo Olympics Opening Ceremony
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