Mathai, the 18-year-old nursing student from Dallas, is in possession of carefree, unique voice. That's why her coach Adam Levine chose Nelly Furtado's 'I'm Like a Bird' for tonight's (April 23) quarterfinals performance on 'The Voice.' Levine was convinced that Mathai was born to sing this song but she needed some persuading. Make that a lot of persuading, actually.

During her performance, she was smiling, an ear-to-ear grin crossing her pretty face. Perhaps she was thinking about how highly her coach complimented her, saying she could eat the song for breakfast, lunch and dinner. She had a breathy tone but still, you could tell she wasn't fully confident when singing this song. But Mathai made up for it by bouncing around the stage as though she owned it; that, dear viewer, is what we call stage presence. The acrobat that hung from the rafters like an avian creature as part of the staging and production was a bit distracting. Even Levine was like, "WTF?!"

There were a few off-key moments during Mathai's rendition of the song, but that didn't detract from her charm. Christina Aguilera sharpened her claws, since this is the quarterfinals and she wants her team to win, pointing out that she didn't believe that Mathai herself connected with the song.

It was a good rendition, but not Mathai's most memorable performance.

Watch Mathai Perform 'I'm Like a Bird' on 'The Voice'