The Take That singer said that he was devastated to see the 19-year-old in the bottom two for a second time last week and argued that she shouldn't try and change herself for the sake of the public.
"I can't tell you how I sad I was last week to see you twice in the bottom two," he commented after Misha's performance of Whitney Houston's 'I Have Nothing'. "I have to say right now, I completely disagree with every person out there watching this show, because I can't believe no-one's voting for you, I really can't.
"The other thing that's making me really sad is that it's actually affecting you and the songs you're choosing and the performance you're giving. You're being too safe, I want Misha B back the way Misha B should be."
He continued: "I feel like you're trying to win votes, get back to how you was because that's how I loved you. And if you're going to go out of this competition like that, who cares, go out with your integrity."
Discussing a "hellish" week that saw her estranged mother attempt to get back in touch, a tearful Misha B then told Dermot O'Leary: "When I started this competition, I set myself up to expect the unexpected, because you just never know what the outcome is. I'm just really grateful to still be here."
The X Factor continues tomorrow (November 20) at 8pm on ITV1.
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