Alesha Dixon takes up a spot behind The X Factor judges' desk for the first time tonight.
The current Britain's Got Talent judge will step in for Nicole Scherzinger at auditions in Manchester this series.
Alesha is standing in for Nicole who was unable to make auditions due to a 'diary clash'.
A source told The Sun newspaper during filming: “Everyone is gutted that Nicole won’t be joining them, but Alesha has a wealth of experience from her role on BGT and her own pop career so will do a great job filling in.”
A spokesperson for The X Factor confirmed: “Alesha is guest-judging for the first day of the Manchester auditions as Nicole is unable to film that day due to a previous diary commitment.”
It's not the first time Nicole has been replaced, with last year's London try outs seeing Mel B stand in for the Pussycat Doll.
Alesha will also be seen stepping in for an ill Sharon Osbourne when try outs visit Edinburgh this evening.
Host Dermot O'Leary said of the guest judge: "She’s good, so fun. I know her pretty well from her Mis-Teeq days - I was a big fan and went to all their concerts! I’ve interviewed her a few times but I’ve never really worked with her properly before in a judging context. She did Louis’ judges houses last year and was really good, super opinionated."
Dermot added: "Poor Nicole came back to, ‘Oh Alesha was very good!’. They were still talking about her just two days ago!
"Nicole knows she’s a great judge though so they can’t wind her up, she’s like, ‘Yeah, whatever!’."
Meanwhile, Simon Cowell revealed that Alesha had originally been due to join The X Factor before appearing on Britain's got Talent.
He said "She was amazing. She was going to be on the show in the first place before BGT.
"She was brilliant; I have to tell you, seamless. I would hire her on my record label, she’s that good."
The X Factor returns to ITV tonight, Sunday 3rd September at 8pm.