|Dates: 23 July-8 August Time in Tokyo: BST +8|
|Coverage: Watch live on BBC TV, BBC iPlayer, BBC Red Button and online; Listen on BBC Radio 5 Live, Sports Extra and Sounds; live text and video clips on BBC Sport website and app.|
Great Britain's world champion Dina Asher-Smith has pulled out of the Olympic 200m after revealing she tore her hamstring earlier this month.
The 25-year-old, who suffered the injury at the British Championships, failed to make the 100m final in Tokyo after running 11.05 seconds in her semi-final earlier on Saturday.
A tearful Asher-Smith told BBC Sport: "It broke my heart because I am a competitor. It is the Olympics but there are plenty other championships for me to come and kill."
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She said she had been in the "shape of her life", but was then close to having to miss the Olympics after suffering the injury after 60 metres of her 100m national title win in Manchester in June.
It was only after getting a second medical opinion on the severity of the tear that she decided to travel to Tokyo and attempt to compete.
In an emotional TV interview, she said: "I'm so grateful to everybody who worked so I could stand here on the track and race here tonight.
"Obviously I was not my normal self, but it has been quite a journey, so I'm really proud. The most frustrating thing is I was in the shape of my life - and I can say that with my hand on my heart.
"If you had asked me six weeks ago, I was confident I was going to win this entire thing.
"I knew every part of my race - my start, transition and finish. They were better than some of the fastest women in the world.
"I am going to pull out, and that is the one as reigning world champion - you know that Olympic champion isn't that much of a further step.
"It doesn't change the calibre of the athlete that I am and I know that if I want to showcase that I just need a few more weeks of power training, a bit more speed endurance to fill that gap of when I was trying to walk again."
Asher-Smith was set to face stiffer competition in the Olympic 200m, which begins on Monday, than she had in Doha two years ago.
American Gabrielle Thomas ran the fastest 200m since legendary world record holder Florence Griffith Joyner at the US trials earlier this year, while Jamaica's Shelly-Ann Fraser-Pryce and Shaunae Miller-Uibo of the Bahamas, neither of whom were in the world final, both competing.
The 25-year-old might still compete at Tokyo 2020 though, after not ruling out racing in the women's 4x100m relay, alongside 100m finalist Daryll Neita.
The heats for the relay are on Thursday, 6 August, with the final the day after, which could give Asher-Smith six days to rest, should Team GB qualify.
"11.05 is incredibly useful in a relay leg, especially with Daryll and we've got a relay to do," Asher-Smith said.
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