Dina Asher-Smith is out of the Commonwealth Games after suffering a hamstring injury at the World Athletics Championships.
Orpington's Asher-Smith claimed bronze in the defence of her 200m title from 2019 in Oregon and claimed she'd never been in better shape.
But she limped off the track after the 4x100m relay - leaving her involvement in Birmingham and next month's European Championships in major doubt.
"I feel good but I’m in need of a few days off," she said.
"But due to the short turnaround between the end of [the] Worlds and the start of the Commonwealth Games in a few days’ time, I’m going to have to withdraw.
"I was so excited to race in front of a home crowd and all the British fans, it’s going to be such an amazing competition and I know that Team England will do you all proud."
Asher-Smith won relay gold and 200m bronze on the Gold Coast, Australia, four years ago and was expected to be one of the star names in the track and field competitions at the Alexander Stadium.
She flew back from Oregon on Monday but scans revealed she needed some time off the track ahead of the European Championships in Munich, Germany, where she remains confident of being involved. Missing a home Games is another injury blow for Asher-Smith, whose Olympic ambitions last year were also derailed by a hamstring problem.
“It’s obviously really sad to lose Dina through injury, given her stature and standing as one of the best female athletes in the world,” said England’s athletics team leader Kelly Sotherton.
"We know just how much she was looking forward to being part of Team England at a home Games in Birmingham. We wish Dina well with her recovery and hope to see her back on the track very soon, doing what she does best.”
Meanwhile, organisers have revealed a number of positive Covid cases following the arrival of the first 1,500 athletes in Birmingham, in total 5,000 will be arriving in the city in the days ahead.
"We have had about a dozen a day and we have had about 1,200 to 1,400 athletes going through our testing process so it's not a huge number," said Commonwealth Games Federation medical advisor Peter Hacourt.
One England athlete has been sent home after they failed a PCR test on arrival, while another has now been cleared to test following further testing.
However, team officials hope the athlete in question - who chose to return home rather than enter an approved isolation programme - will still have a chance to post a negative sample and return for their event.
"With the levels they are showing we are pretty confident they will be back in play again," said chef de mission Mark England, who admitted further positive tests were 'inevitable' because of the prevalence of the virus.
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