The My Heart Will Go On hitmaker recently invited Ne-Yo back into the studio after previously hiring him as a songwriter for her 2007 album Taking Chances, and they ended up recording a song together for her forthcoming release, Water and a Flame.
Ne-Yo, who has also penned hits for Beyonce, Whitney Houston and Enrique Iglesias, admits the experience was unlike any other and he found himself doubting whether he could hit the high notes as well as Dion.
He tells DigitalSpy.com, "The first time I worked for her I wrote a song for her, which in itself was surreal. This time around I actually did a duet with her - it's her and me on one song, which was a challenge to say the least! I was trying to figure what I was even doing there - why would they need my voice when they have hers?
"She wanted to do the song as a duet and I was flattered, but it definitely made me question my vocal ability."