European 800m bronze medallist Becky Lyne has pulled out of Great Britain's squad for the World Championships in Osaka after aggravating a calf injury.
Lyne was one of the best performing British athletes last season
Lyne had just returned from the same injury and was due to run in Manchester on Saturday night but had to withdraw.
Her place in Osaka is likely to go to Jenny Meadows, who has beaten her twice over the distance at recent events.
"I have been trying to wrestle through," said 25-year-old Lyne. "But I think I have made it worse."