Four previous 'X Factor' winners will be excluded from the show's 10th anniversary special later this month.
The Sun reports that this year's contestants will be singing the songs of previous stars in a special edition of the ITV talent show, but Steve Brookstein (2004), Shayne Ward (2005), Leon Jackson (2007) and Matt Cardle's (2010) musical efforts have all been left out.
Steve Brookstein, Shayne Ward, Leon Jackson and Matt Cardle
Instead the likes of Sam Bailey and Tamera Foster will belt out songs by more successful winners such as Leona Lewis (2006), Alexandra Burke (2008), Joe McElderry (2009), Little Mix (2011) and James Arthur (2012).
A show source told The Sun: “With such a massive roster of successful artists from the past ten years, not all winners could be included in the final song choices.”
But an insider added: “It is a slap in the face for the winners who won’t be covered.
"Bosses have obviously chosen the former stars who they think still resonate with viewers and who have had the most success."
It isn't the first time that 'X Factor' bosses have written Steve, Shayne, Leon and Matt out of the show's history.
Earlier this year, they were not featured in a special 'X Factor' advert, mashing up the biggest hits spawned by the show.
Matt Cardle voiced his disappointment at the time, telling Unreality TV: "I was a bit disappointed not for myself but for the fans who'd voted for me.
"The year that I won 'X Factor' was the highest ratings they've ever had. Something like 19.5 million people watched the final that year."
'The X Factor' airs its 10th anniversary celebration on Saturday 23 and Sunday 24 November.