'Skyscraper' singer Sam said the 24-year-old popstar is simply too young to be giving advice to wannabes.
She told The Sun: "It's not that I don't like Rita, I just don't think she has enough experience to tell me what I already know. Rita hasn't been on the pub circuit, she went to drama school and was groomed to be famous before she left.
"Yes she's a great performer but would I want her mentoring me? No. I've been performing for 20 years."
After winning The X Factor in 2013, Sam achieved a Number 1 Christmas hit with 'Skyscraper' and followed that with her chart-topping debut album, The Power of Love.
Her chart success was followed by a UK tour, but in February this year she was dropped from Simon Cowell's Syco record label.
Mum-of-three Sam added: "All I wanted was the chance to get a career I love. I've got that and am happy with that. I'm happy just to plod along."
This week, Sam also hit out at Simon, saying she "feels sorry" for last year's winner Ben Haenow because she thinks Simon is planning on making runner-up Fleur East "the next big thing".
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