The former Spice Girl was noticeably absent from yesterday's X Factor press conference with media and a spokesperson for ITV has said: "There is a chance Mel she won't make it, absolutely."
Mel had been scheduled to join her fellow judges – Cheryl Fernandez-Versini, Simon Cowell and Louis Walsh – at a press conference in London on Thursday, but was unable to make it.
Reveal was at the press conference where journalists were simply told Mel was unwell. No further detail was given.
According to Daily Star, Mel is feeling so under the weather that she's been unable to spend much time with her finalist Andrea Faustini, as she's worried she may pass her illness on to him ahead of the final.
A source said: "Mel can't help it. She is so poorly and may have to miss the final altogether."
This is Mel's first year as an X Factor judge in the UK, and it's already been a success as she mentored Italian singer Andrea to the final.
He will go up against Simon Cowell's contestants Fleur East and Ben Haenow.
X Factor's finale weekend airs across Saturday and Sunday on ITV. As well as the finalists' performances, we'll see special appearances from One Direction, Take That, Ed Sheeran, Sam Smith, Meghan Trainor and Olly Murs and Demi Lovato.
The finalists will then have time to breathe over Christmas before embarking on The X Factor Live Tour, which kicks off 13 February in Belfast.
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