Head judge Simon didn't get off to the best start with Mason, who during the Six Chair Challenge complained about the amount of airtime he had been given, which led Simon to brand Mason a "complete a*sehole".
Mason dropped his mic and stormed off stage, but after contestant Tom Bleasby quit, Nick Grimshaw made the controversial decision to bring Mason back a week later to appear at Judges' Houses.
Mason impressed mentor Nick, and last weekend we saw he was picked by Nick to go through to the next stage - the live shows.
The decision, however, was met by boos from the studio audience.
Speaking to Alan Carr on Chatty Man (which will air tonight), Nick says Mason has to "turn around the country" but reveals Simon has already labelled him a "star".
Nick says: "He [Mason] is already getting boos. He is good though! When I said he was going through on Sunday night everyone was really booing him so I thought am I losing my mind? Was he really bad? Then I watched it back and it's not really that bad.
"He just argued with Simon Cowell who starts arguments with everyone but no one argues back. I think he did handle it wrong but he came back and he was really humble and he apologised. He is super lovely and Simon has forgiven him and Simon is like 'He's a star'. Simon loves him now so hopefully everyone else will love him."
Nick adds: "He is probably the most dedicated one on it now he knows that he has got to try and turn around the country. He has got such good vision of who he wants to be so that is why I had to trust him."
Mason recently spoke out about Simon, saying the pair had cleared the air.
He told The Sun: "[Simon] rang me. We had a little conversation, like, 'There's no hard feelings there, there's no bad blood, no-one's upset'. Respect from artist to artist. He's the big man, the big boss."
Chatty Man airs tonight (Friday 30 October) at 10pm on Channel 4.
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