Christina is one of the favourites to win The Voice this year but was given a no on the ITV series back in 2008.
Then aged just 15, Christina had sung for Cheryl Cole, Simon Cowell, Louis Walsh and Dannii Minogue.
It was the same year that JLS auditioned and Christina admits it's weird to once again be hanging with the band's Marvin Humes... not that he remembers her!
"I did The X Factor when I was 15. So it’s weird seeing Marvin again because he and I stayed in the hotel when he was setting out with JLS," Christina said.
The Bristol-born singer told the Metro newspaper: "He doesn’t remember me but I remember him because I thought he was pretty cute."
Christina isn't the only one of this year's acts to have tried their luck before with her former Team Ricky rival Emily Adams revealing how she was ditched by Britain's Got Talent.
“I sang Summertime and there was a big high, long ending note at the end which Simon Cowell stopped midway,” she said. “I was like ‘Oh my God! He’s stopped the song’. He said it lacked emotion but I did get four yeses.”
But the girls' fellow Voice contestant Lee Glasson has claimed he vowed NEVER to audition for The X Factor.
“I always said I’d never do X Factor,” Lee said last week. “I don’t like the format and what it stands for.
“Watching The Voice I could see they would go in, come out and still be themselves.”
Lee added: “My instincts were correct – no one is trying to make me something I’m not. ”
The Voice UK continues with its live semi-finals this Saturday night on BBC One.
Browse pictures of last night's performances on The Voice UK below...