Olly Murs is reportedly set to replace Gavin Rossdale as a judge on "The Voice".
The 33-year-old singer is set to join the ITV talent shows judging panel alongside Sir Tom Jones, Jennifer Hudson and will.i.am, following the Bush band member's departure.
The "Troublemaker" hitmaker co-hosted "The X Factor" alongside Caroline Flack in 2015 after having competed on the programme in 2009, but it is believed Olly's new venture has upset Simon Cowell who thinks the musician has "swapped allegiances" if he works on his rival show.
Speaking about Olly's next role to The Sun Online, a source said: "Simon isn't happy Olly's swapped allegiances, especially as he left the X Factor to concentrate on his music."
However, Olly's new project will be different to his time presenting "The X Factor" when he had to remain "impartial", as he will be able to comment on the budding artists and their performances, as well as mentor them throughout the series.
The insider explained: "It won't be like when he presented X Factor when he had to remain impartial."
The news Gavin - who has Kingston, 11, Zuma, nine, and Apollo, three, with his former partner Gwen Stefani, as well as 28-year-old Daisy Lowe with Pearl Lowe - had been axed from the chair-spinning show came earlier this year.
And it is believed the reason the "Love Remains The Same" hitmaker was booted off the programme was because "The Voice" bosses felt he lacked charisma and were keen to recruit someone who had "serious spark".
Speaking previously about Gavin's departure, a separate source said: "Gavin was great to work with during the series, but the bosses just felt he wasn't right in the end.
"He didn't make much of an impact, and they want someone with serious spark and charisma.
"So they have taken the decision that he won't be back next year."