|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.|
British sprinter Adam Gemili's hopes of a medal in the men's 200m at the Tokyo Olympics were dashed as he pulled up injured in the heats.
Gemili, 27, had been aiming to improve on his fourth-placed finish at Rio 2016 where he missed out on bronze by three thousandths of a second.
A clearly distraught Gemili stopped immediately after leaving the starting blocks before walking to the finish.
"I can't believe this has happened. I am in so much pain," he told BBC Sport.
"In my last block start before I went into the cool room and I just felt my hamstring go. I just said strap it up and let me go out there and try, because you have to try.
"I felt like I had such a good chance as well. I have been training so well. This season has been really up and down and I had finally put together five to six weeks of solid work.
"I was ready to go out and win, try and get a medal, at least PB and I don't get that chance. I can't say anything else. It is the worst feeling in the world."
Fellow Briton Nethaneel Mitchell-Blake, who clocked a season-best time of 20.56 seconds, also failed to advance to the semi finals.
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Gemili, who is participating in his third Games, was also due to compete for Great Britain in the men's 4x100m relay heats that begin on Thursday.
His likely withdrawal continues a difficult Olympics for Team GB sprinters.
Zharnel Hughes was disqualified in the men's 100m final after Reece Prescod also false started in the semi-finals, while Dina Asher-Smith failed to make the women's 100m final and pulled out of the 200m after tearing her hamstring in July.
Sawyers & Irozuru miss out as middle-distance trio advance
A month after breaking Kevin Young's 29-year world record, Norway's Karsten Warholm ran a stunning men's 400m hurdles race to obliterate his own mark as he took gold.
GB's Jazmin Sawyers and Abigail Irozuru missed out on the medals in the long jump final as Germany's Malaika Mihambo took gold.
Sawyers finished in eighth position with a best jump of 6.80m while Irozuru came 11th with 6.51m.
Earlier on Tuesday, Josh Kerr, Jake Wightman and Jake Heyward all safely progressed in the men's 1500m heats.
The trio will now take part in Thursday's semi-finals as they bid to win a first medal for Britain in the event since since Peter Elliott took silver at the 1988 Games in Seoul.
"It's the most nerve-racking round isn't it? You're worried you're going to be embarrassed," said Wightman
"I'm glad I managed to stay on my feet and get through."
In the women's 400m, Jodie Williams confidently won her heat to move into the semi-finals as she underlined her potential since stepping up in distance.
The 27-year-old will now face the Bahamas' defending champion Shaunae Miller-Uibo in her semi-final on Wednesday.
Ama Pipi also advanced as a fastest loser in a heat dominated by 2016 silver medallist Allyson Felix.
However, there was despair for Scottish 23-year-old Nicole Yeargin, who was disqualified for a lane infringement.
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