Tokyo Olympics: Elaine Thompson-Herah stays on course as Laura Muir progresses

Jamaican Elaine Thompson-Herah is on course to complete a sprint double after equalling her personal best to qualify for the women's 200m final.

The 100m champion clocked 21.66 seconds to lead the qualifiers for the final, with silver medallist Shelly-Ann Fraser-Pryce also safely through.

British pole vaulter Holly Bradshaw reached her final after a rain-interrupted qualification.

Laura Muir and Katie Snowdon advanced to the semi-finals of the 1500m.

Thompson-Herah looked impressive in her race but will be challenged in the final by Fraser-Pryce, Marie-Josee Ta Lou of Ivory Coast and impressive Namibian teenagers Christine Mboma and Beatrice Masilingi.

Beth Dobbin, Britain's sole representative in the event after Dina Asher-Smith's withdrawal through injury, finished fifth in the same semi-final as Thompson-Herah, clocking 22.85.

"I don't feel like I belong in that company if I'm honest," Dobbin said.

"It feels so bizarre. I do have to pinch myself every time I run with these girls, but I am getting more used to it. This year's been the first year when I've been on the Diamond League circuit and it's been really good to get that experience.

"This morning helped me a lot because it didn't faze me I was running with Elaine. I've done it a few times now and she was in my race when I PBed so I was hoping for that today. These girls are my idols and I'm just living the dream."

Shericka Jackson, the 100m bronze medallist, failed to make it to the semi-finals after dramatically easing down too soon in her heat, missing out on qualification by four one-thousandths of a second.

Muir gets campaign under way

Muir said she is "more prepared than ever" after finishing second in her heat in four minutes 3.89 seconds.

Having decided not to compete in the 800m, her Tokyo campaign started with a routine heat as she came home behind Canada's Gabriela DeBues-Stafford, with Ireland's Ciara Mageean fading late on to finish 10th.

"It's really nice to get that first run out of the way and feel comfortable," said Muir, who was seventh at Rio 2016 and fifth at the 2019 World Championships.

"I am more prepared than ever. I have improved so much. I am in the best condition I could be and hopefully any situation I can deal with."

In a dramatic moment, world 1500m champion Sifan Hassan fell with 400m to go but won her heat in 4:05.17.

The Dutchwoman, who was born in Ethiopia but represents the country where she arrived as a refugee aged 15, later went on to win gold in the 5,000m final to complete the first part of a 1500-5,000-10,000m treble.

In the pole vault, Bradshaw, who is aiming to win her first major championship medal outdoors, needed just one attempt at 4.55m to secure her place in Thursday's final.

But Rio 2016 silver medallist Sandi Morris of the United States did not progress.

"It's the dreamy way to qualify - just do one jump and save energy," said Bradshaw. "I've never experienced anything like that in my life, it was the worst conditions I have ever had.

"There were lots of run-throughs, lots of people close to hurting themselves. Sandi actually hurt herself and it could have been a lot worse, but to lose someone like her from the final is a massive loss and I am gutted for her that she can't defend her medal.

"It was a bloodbath and it was just about whoever could keep your head in the game and keep your body in the right place."

Jess Turner missed out on a place in the 400m hurdles final, finishing seventh in her semi-final after a flare-up of an Achilles injury.

"It was too painful, limping over the finish line wasn't how it wanted it to end," said the 25-year-old. "But I just couldn't run through it. I was thinking adrenaline would kick in, but I just couldn't.

"I need to get home and get this sorted out. I never want to experience this again, especially at a Games. But I am proud to be here and happy I made the semis but sad it had to end this way because I genuinely thought I had a shot at the final if I had run like I have been running all season."

Allman triumphs and Greek gold

Valarie Allman won the USA's first track and field gold of the Tokyo Games with gold in the women's discus.

Her throw of 68.98m in a rain-disrupted final was enough to beat Germany's Kristin Pudenz (66.86) and Cuba's Yaime Perez (65.72) with two-time defending champion Sandra Perkovic of Croatia fourth.

In the women's 100m hurdles final Jasmine Camacho-Quinn won Puerto Rico's first ever track and field gold by powering home in 12.37 seconds, edging out America's Kendra Harrison (12.52) and Jamaica's Megan Tapper (12.55).

"For such a small country, to give little kids hope, I'm just glad I'm the person to do that," Camacho-Quinn said afterwards.

In a dramatic final round of the men's long jump final, Greece's Miltiadis Tentoglou used his last effort to jump 8.41m.

The mark tied that of Juan Miguel Echevarria but Tentoglou took gold by virtue of his second-best jump on the day being longer than that of his Cuban rival.

Echevarria had one more chance to leap to gold but pulled up with a hamstring problem on his run-up.

And Soufiane El Bakkali of Morocco won gold in the men's 3,000m steeplechase, breaking Kenya's stranglehold on an event they had won nine times in a row.

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