Bettencourt tells Guitar Interactive: "Whatever people's perceptions are of whatever Rihanna is, it's definitely a different animal live - completely different. At first, even when I went to work with her, I was, like, 'Can she really sing?' A lot of times with the singers you hear now, there's a lot of that auto-tune element and you don't know who can really sing. But when I went to rehearsal, I could not believe how well she sang, and I could not believe how well she sings live.

"People ask me, 'Why would you do something that you can do with your eyes closed?' And it's a difficult gig. The hats that you have to wear, feel-wise - you go from a basic pop song like Umbrella to a reggae song to a club track to even, like, a punk song and R&B stuff.