The tracking week for the festive chart begins tonight at midnight, with sales and downloads registered before 23:59 next Thursday contributing towards the all-important rundown; with the Christmas Number One victor being crowned on Friday, December 22.

Sheeran’s Perfect has long been the bookies’ frontrunner: it’s the current Number One, and new versions by Beyonce and - as of tomorrow - Andrea Bocelli have only strengthened its performance.

But now, at the last minute, has a last minute challenge been mounted by Adele?

Oddschecker have told Express.co.uk of a flurry of bets being placed on the megastar, resulting in her odds being dramatically shortened from 22/1 to 2/1 - making her the second favourite.

She doesn't appear to have any tracks currently gaining traction on iTunes or Spotify - so could this be relating to internet rumours that she'll release her cover of George Michael's Fastlove?

Oddschecker spokesperson George Elek said: “This has been a curious gamble considering there isn’t even a song of her charting at the moment. 

“It will mean one of two things; somebody knows more than the market, or it's the blind following the blind! We'll soon find out.”

Rumours first circulated that Adele would release Fastlove a couple of weeks ago, but it did not come to fruition. Could this now be the time?

In the meantime, Ed Sheehan is still ahead in the market, with 4/6 odds. Other competitors include Wham!, after a campaign launched to finally get Last Christmas to No1, and X Factor winners Rak-Su.

Mariah Carey could also go all the way, as All I Want For Christmas Is You continues to score astronomical streaming numbers.

Last year’s Christmas Number One came from Clean Bandit and Anne-Marie with Sean Paul with their track Rockabye.

Christmas Number One 2017 will be announced by the Official Charts Company on Friday, December 22.