Mary Byrne and Matt Cardle are reportedly in danger of missing the X Factor semi-final because of vocal problems.
In previous series acts such as Diana Vickers have been given byes after falling ill during the competition, but it has never happened at such a late stage in the TV talent show.
Cardle's illness is so bad that he was forced to miss out on a planned TalkTalk secret gig earlier this week, where the five remaining acts did a short Q&A with fans.
Byrne did perform at the London show but has apparently since lost her voice.
A source told the Daily Star: "Matt is putting a brave face on things but his voice is in bad shape and he could miss the semi-final. He's really low because he's desperate to be at his best for such a vital show. Mary and Matt have both been struggling with their throats for the past week.
"Matt was advised to rest his voice by doctors and so didn't perform. Mary did sing but complained of a bad throat afterwards. At the moment we're hoping they will be fit to appear but we just don't know. It will be a disaster if they have to pull out."
Meanwhile, One Direction may be without Zain Malik on tomorrow's show, because the singer has returned to Bradford due to a "family health matter".
The X Factor semi-final kicks off on Saturday at 7.40pm on ITV1.
Now how the heck are they going to get round that....