Going into rehearsals with his coach, Vangelis reveals he was going to be performing Spice Girls' Viva Forever.
"It's a massive opportunity and I don't want to waste it," says Vangelis, "Song choice is definitely key, it needs to be right."
However Boy George wasn't immediately raving about the selection.
"I just felt like he wasn't blown away by it so I was a bit like 'I don't know if he's got it or not'," Vangelis explains, "It was just a bit of shock, it did throw me a bit.
"We did decide to change the song."
"It was undeniably the wrong song,"says George
"It's certainly better than Viva Forever," adds The Voice coach of the new song choice. "People are going to gasp and love this song."
"It isn't an ideal situation but I think it's going to keep him on his toes and I'm excited about what he's going to do," George remarks.
Despite having to rehearse another song, Vangelis says: "I feel really happy about the song change."
Another song choice that doesn't convince Boy George is Harry Fisher's selection with the Culture Club hitmaker worrying that the performance could turn into "karaoke".
Others fighting for a place in the live shows on Team George this weekend are Cody Frost Laura Begley, Chase Morton, Leighton Jones, Bradley Waterman and Alaric Green.
The Voice UK airs this SUNDAY night on BBC One from 7:45PM.