Dina Asher-Smith in danger of missing 2017 World Championships

Dina Asher-Smith is in danger of missing this year's World Championships in her home city of London due to a broken bone in her foot that will require a long period of rehabilitation.

The 21-year-old sprinter, who won Olympic bronze as part of Britain's 4x100 metres women's relay team at the Rio de Janeiro Olympic games in 2016, suffered the injury after landing awkwardly in training last month.

The issue forced Asher-Smith to pull out of the recent Indoor Grand Prix in Birmingham but her coach, John Blackie, believes the issue is more severe.

"It's going to require a bit of treatment, let's put it that way," Blackie told the Daily Mail.

"Things will come clearer once we've got through this week. It's difficult to say whether she'll be okay for London because it depends how well the rehab goes.

"Some people rehab quickly and others a lot slower. But we won't do it by luck. It's a long-term picture, things shouldn't be rushed just for the sake of an event, the athlete comes first. That's always the case."

Asher Smith appears more upbeat about the knock, insisting she "heals quickly" and now is a better time than May to get injured.

She said: "The injury is so annoying. I was doing jumps in the gym and landed badly.

"When I tried to stand, I couldn't put weight on it. But I have enough time to make a full recovery and get some training in before the outdoor season.

"If it had to happen, better now than in May. I usually heal quickly."