Day 1 of track and field at the Tokyo Olympics was Friday in Japan, or Thursday night into Friday morning stateside.
The only final of the day was in the men's 10,000m.
Other notable events included: the first rounds of the men's 400m hurdles, women's 100m, women's 800m, men's steeplechase in the earlier session, followed by first rounds of the inaugural mixed 4x400m relay and women's 5000m in the later session, leading up to the men's 10K.
Prelim Round (8pET)
1st Round (11:15pET)
This round of races perhaps already provided enough evidence to declare Olympic Stadium in Tokyo the home of a "fast track."
Six women went sub-11 in the women's 100m heats, led by Ivorian Marie-Josee Ta Lou's personal-best 10.78 to win heat four — the time trimmed nearly a tenth of a second off her previous top mark from 2018. Here are the others:
10.78, Marie-Josee Ta Lou, CIV (heat four winner)
10.82, Elaine Thompson-Herah, JAM (heat two winner)
10.84, Shelly-Ann Fraser-Pryce, JAM (heat five winner)
10.91, Ajla Del Ponte, SUI
10.95, Mujinga Kambundji, SUI
10.96, Daryll Neita, GBR
Video: Jamaica's Thompson-Herah crushes 100m prelim, moves to semis
Video: Jamaican Shelly-Ann Fraser-Pryce commands 100m heat in 10.84
Men's High Jump
All three podium finishers from the 2019 World Championships made it through: two-time Olympic medalist Mutaz Barshim of Qatar, and the ROC's Mikhail Akimenko and Ilya Ivanyuk.
American JuVaughn Harrison, 22, attempting the high-long double, also qualified for the final.
1st Round (8:30pET)
Ethiopia's Lamecha Girma , the 2019 world silver medalist, clocked the event's fastest-ever heat time at the Olympics in 8:09.83. Behind him in second in heat one was 19-year-old Ryuji Miura of Japan, who broke his own national record in 8:09.92.
Kenya's Abraham Kibiwot and two-time world medalist Soufiane El Bakkali of Morocco were the winners of heats two and three in 8:12.25 and 8:19.00, respectively. U.S. champion Hillary Bor took sixth in heat two and was eliminated. Other national champs also missed the cut: Kenya's Leonard Bett and Ethiopia's Bikila Tadese Takele.
1st Round (9:25pET)
The American contingent of 19-year-old Athing Mu, 2019 world silver medalist Raevyn Rogers and American record-holder Ajee Wilson advanced successfully to the semifinals — the former two, making their Games debuts, won their respective heats. Cuba's Rose Mary Almanza, Jamaica's Natoya Goule and France's Renelle Lamote also won.
Men's 400m Hurdles
1st Round (10:25pET)
Qatar's Abderrahman Samba, world-record holder Karsten Warholm of Norway and American Rai Benjamin – the 2019 world medalists – all won their respective heats to advance.
Video: Benjamin cruises to 400m hurdles first-round heat victory
1st Round (6aET)
Netherlands' Sifan Hassan, who's attempting the 1500-5K-10K triple, comfortably won heat one in 14:47.89, while Kenyan Hellen Obiri, the two-time reigning world champion and 2016 Olympic silver medalist, took second to world leader Gudaf Tsegay of Ethiopia in heat two, 14:55.77 and 14:55.74, respectively.
Video: Ethiopia's Tsegay, Kenya's Obiri go 1-2 in women's 5K prelim
Women's Shot Put
Twenty-one-year-old Selemon Barega, the 2019 world silver medalist, held off world record-holder Joshua Cheptegei of Uganda to return Ethiopia atop the podium for the first time since the back-to-back eras of Haile Gebrselassie and Kenenisa Bekele, who together took home four straight Olympic golds for the East African nation from 1996 to 2012.