Rachel Stevens injured ahead of Strictly Come Dancing final

The former S Club 7 star, who is a favourite to win the competition, hurt her back in a fall during practice with partner Vincent Simone.

It is understood Miss Stevens, 30, is undergoing emergency treatment in order to be well enough to appear on the programme.

A source on the show said: "Rachel is having emergency physio and is taking pain-killers. It couldn't have come at a worse time because she's desperate to be fully fit for the final.

"She has been struggling with her back and all the lifts haven't helped. However, she really jarred it after falling heavily. It's a real shame.

Rachel is the bookmakers' favourite to scoop the dancing prize at odds of 6/4, ahead of Holby City star Tom Chambers and model and presenter Lisa Snowdon.

The programme has already faced a storm after a voting controversy last weekend. All three couples were put through after the judges' votes meant that Chambers could not be saved – even with the help of the public telephone votes.

The BBC decided to scrap all votes, prompting 1,687 viewers to email a complaint and 193 to telephone in. The corporation said it would offer refunds to viewers and the "fairest option" was to allow the combined scores of the judges and audience to carry over to the first of two shows.

Judge Craig Revel Horwood blamed fellow judge Len Goodman for the voting fiasco because his "mean marking" of Rachel Stevens resulted in her tying at the top with Miss Snowdon, 37.

- telegraph.co.uk