Katarina Johnson-Thompson's Olympic dream is in tatters after her injury nightmare surfaced again in Tokyo.

The world champion ruptured her Achilles in December but it was her calf that was unable to take the strain of her first major heptathlon since as she pulled up during the 200 metres.

Johnson-Thompson refused treatment and a wheelchair on the track to pick herself up and finish the race, limping over the line, but was disqualified for leaving her lane after falling.

The 28-year-old was spotted having treatment on her Achilles between jumps in the high jump on Wednesday morning and seemed to be limping then.

She fought back from the serious injury and surgery in December and had downplayed her medal chances but was sitting fifth after three events before disaster struck with around 100m to go.

It was due to be her first full heptathlon since winning the world title in Doha in 2019 due to the pandemic and injury but her Olympics are likely to be over, with her medal hopes gone anyway.

Her disqualification left her last and 1,082 points behind overnight leader Anouk Vetter. Defending champion Nafi Thiam sits third.

Johnson-Thompson dropped to fifth after the shot put, her first event of the night, and was 139 points adrift of Thiam, although only 45 off Noor Vidts in third.

She had opened the morning with a strong 100 metres hurdles winning her heat in 13.27 seconds – her second fastest time ever.

In the high jump she cleared 1.86m – 12cm off her personal best – and failed at 1.89m to leave her with 2138 points.

It was more injury woe for Team GB on the track as Dina Asher-Smith had already pulled out of the 200m having failed to make the 100m final. She revealed she had been battling a serious hamstring injury suffered in the trials in June.

Adam Gemili also tore his hamstring at the last minute before his 200m heat and walked the race.

Great Britain have won just one medal at the Olympic Stadium so far, Keely Hodgkinson's impressive silver in the women's 800m.

Former Olympic heptathlon champions Denise Lewis and Jessica Ennis-Hill expressed their devastation for Johnson-Thompson.

Speaking on BBC Two, Lewis said: "I'm just so gutted for her. So gutted for her. She's worked so hard to get to this stage."

Ennis-Hill said: "She had the best year of her life in 2019, she was ready to go. When you're in that position, going into an Olympic year, that's the best place you can be – you just need to ride through the winter, maintain that form, and you're at the Olympics.

"The event is so gruelling and it's ended up in injury. It's utterly, utterly devastating for her."

Laura Muir at least reached Friday's 1500m final with little fuss after she clocked four minutes 00.73 behind favourite Sifan Hassan.

The Scot looked strong after moving into the top three early and was untroubled in the final lap.

She said: "Everyone always talks about the final but you have to get there first. To make an Olympic final is still a very big achievement and I'm very happy I'm there now and can look forward to Friday.

"I saw we were clear at the end so I eased down a bit. I saw the first semi-final was quite quick so the fastest loser spots were going to be tough. I didn't want to get pipped on the line and wanted to keep out of harm's way."

Jodie Williams reached the women's 400m final after running a personal best of 49.97 seconds.

In the morning session Andrew Pozzi made the 110m hurdles final for the first time in his career.

The world 60m champion finished fourth in his semi-final in 13.32secs and had to wait to see if he would qualify as one of the fastest losers.

He reached the semi-finals in Rio five years ago and the 29-year-old admitted it was a nervous time to see if he made it through to Thursday's final.

"That wait was horrible, excruciating. It's the first time I've had to go through that wait, hopefully it will be the last, and I'm so happy to make the final," he said.

"I feel like I'm growing in this competition, I felt much more comfortable on that run, and I'm really confident that tomorrow will be better again. I'm really happy to have the opportunity to do more."