Kimberley Walsh is undergoing physio to get her in shape for this weekend's Strictly Come Dancing after damaging her knee.
She is thought to be suffering from an injury common to runners - iliotibial band syndrome - and has been having eye-watering treatment for the past few days.
The Girls Aloud star said she had her "fingers crossed" she would be up to full fitness to perform a salsa on this weekend's show with professional partner Pasha Kovalev.
It is the latest injury to beset this series following Aliona Vilani's damaged ankle - which put her out of the show - and James Jordan's broken nose.
Kimberley revealed her problems as she attended the Cosmopolitan Ultimate Women Of The Year event last night.
She said: "I've got a little bit of a bad knee which is causing me a bit of trouble, but I'm getting physio every day and I'm crossing everything that I'll be able to salsa this weekend, so fingers crossed."
She added that, other than her injury, "training's going well".
A show source said: "Kimberley's been suffering with a knee injury and has been training with it strapped up. Pasha's been an absolute saint in helping her continue dancing and she has seen a physiotherapist this week, who has been working wonders.
"She is dancing a salsa this week - so, fast with lots of twists and turns which aren't helping her knee. She is determined to train through the pain because she loves her dance this week, and hopes her knee will hold out."
On last Saturday's show Kimberley pulled off her best dance of the series, landing 31 points from the judges which put her in joint second place behind Louis Smith.