Rachael wows on X Factor

Rachael Thompson. Picture: Supplied

It was a performance that won a standing ovation from the audience and was called the "best audition ever" by the four X Factor judges.

But when Melbourne schoolgirl Rachael Thompson stepped out on stage in last night's episode, she was only thinking about her song.

"It was very nerve-racking before I got on stage," the 14-year-old told Access All Areas about her first audition.

"I had sweaty palms and all that but as soon as I got on stage it was like it was only me and the four judges in the room. I couldn't hear anyone else - the only thing I heard was the first couple of screams and that was it."

It was only when she saw veteran judge Ronan Keating leaped up to embrace her that Thompson realised how much of an impact her rendition of Please Don't Say You Love me by Gabrielle Aplin had made.

"It was so surreal - the whole reaction, the standing ovation and then Ronan getting on the desk and coming on stage and hugging me," she said.

"I was just blown away that people liked me that much."

Singing from the tender age of 18 months, Thompson has progressed to playing guitar and writing her own music.

She admitted it was her dream to win the Seven talent show and doesn't think her age will prevent her from being taken seriously in the competition.

"I have always been around older people my whole life so I have grown up with mature people," Thompson explained.

"I don't think my age really means anything."

Like many teens her age, Thompson is a die-hard One Direction fan, her room plastered in pictures of the British boy band.

With the group making guest appearances on the show in the past two years, the singer said she would "flip out" if she had the chance to meet her idols during the contest.

"I would probably act cool in front of them but as soon as they left I would break out in tears and start hyperventilating," Thompson laughed.

"To be as famous as them would be amazing. Having so many dedicated fans would be awesome."