X Factor judge Mel Blatt warned Joe Irvine: 'Natalia Kills might pick on you'

X Factor judge Mel Blatt has revealed she suspected axed judges Natalia Kills and Willy Moon might act up during contestant Joe Irvine's performance.

The judges were booted from the show last week after Kills accused Irvine of being a "doppelganger" of her husband Willy Moon, who went on to compare the contestant to Norman Bates from the movie Psycho.

Blatt tells this week's edition of Woman's Weekly that she spotted Kills laughing during rehearsals and became concerned she might pick on Irvine.

"I had pre-warned him. I said, 'I think Natalia might pick on you so be warned, keep your composure, don't listen and just say thank you.'

She also revealed that Irvine's 'mood board' - which the show's stylists use to construct a contestant's look - included pictures of Frank Sinatra, David Beckham - and Willy Moon.

"The vibe of it was like the Rat Pack in the 1950s, which is a look that Willy also does," she explained to WW.

Following the outburst, Blatt says Irvine has to step up his game to prove he's worthy of the support he has received from high profile names such as Ellie Goulding and Ed Sheeran.

Meanwhile, former NZ Idol judge Paul Ellis has also spoken out against Kills and Moon's bad behaviour and believes this is the end of their careers.

"Both have been dropped by their record labels, so they came here on the premise of trying to resuscitate their careers and actually they've snuffed them out," he told Woman's Day.

The rogue judges have since been replaced by I Am Giant rocker Shelton Woolright and former Neighbours star Natalie Bassingthwaite.

- nzherald.co.nz