They added: "We think he could really own it and his voice has the perfect tone for a song like that. We know he will smash it!"
Sam Smith, Emeli Sandé, The X Factor winners Little Mix and former The X Factor judge Tulisa Contostavlos also all picked songs for contestants, with Sam working with Andrea, Mel's second remaining competitor.
"I worked with Sia about 6 months ago and I remember being in the booth with her and her voice is just ridiculous, and when I heard Andrea’s voice for the first time I remember feeling that same kind of reaction", said the Stay With Me singer.
"[Chandelier] is so difficult to sing but I genuinely from my heart think Andrea can do this. This is a huge, huge challenge and I think you’ve got to challenge yourself. Everyone I know loves that song, and everyone I know loves Andrea."
Cheryl Fernandez-Versini's hopeful, 17-year-old Lauren was hand-picked by Little Mix to sing Clarity by Zedd, with the four-piece female group saying: "We thought hard about the kind of artist that Lauren is and what kind of song would really show off her voice, and Clarity was the one we landed on."
Fleur, Simon Cowell's last competitor, and Stereo Kicks, Louis Walsh's eight-piece boyband, will sing A Fool in Love by Tina Turner and Just The Way You Are by Bruno Mars, respectively.
For their second songs of the evening, the five remaining singers will perform a song each chosen by the British public.
Andrea will sing Hero by Enrique Iglesias,Ben Thinking Out Loud by Ed Sheeran, Fleur will take on If I Ain’t Got You by Alicia Keys, Lauren Don’t You Worry Child by Swedish House Mafia, and Stereo Kicks will serenade with Run by Snow Patrol