Since Harry shot to stardom on the talent competition five years ago, he and Nick have formed quite the bromance, so if anyone is going to have the Radio 1 DJ's back when it comes to his new role, Harry will.
Speaking to The Sun, Harry gave his verdict on Grimmy's addition to the X Factor panel. He told the paper: "I think it's brilliant he's been chosen, he's going to be really good."
After months of speculation, Nick was finally confirmed as a judge for this year's X Factor alongside Rita Ora. And while some were excited to see the 30-year-old in the lineup, others questioned Simon Cowell's decision to hire him.
Music mogul Simon has since defended his choice to have Nick on the show, insisting he likes to keep the judging panel varied.
"I have an issue with artists judging other artists," he said. "I would never allow a group of artists to run the record label, that would be crazy. You have to balance it up a bit."
Now, Harry has insisted Grimmy will do a fab job alongside Rita, Simon and Cheryl Fernandez-Versini, claiming people have no idea how much Nick really knows about the music industry.
"What does he bring that isn't already on the panel? He watches it a lot," Harry added. "He knows a lot. You don't necessarily get his total knowledge solely from the radio show, but he knows so much about music."
Nick, meanwhile, hasn't let the criticism about him get in the way of his X Factor experience and he has wasted no time settling in.
Since auditions kicked off in Manchester last month, Nick has constantly been sharing selfies, along with snippets of behind-the-scene action for his fans to see (including Cheryl's first attempt on a skyboard!).
It's also been said he has made a good impression on the panel and has already shown great chemistry with boss Simon on the show. We're not so sure he's been such a hit with this year's X Factor hopefuls, however, as Nick isn't holding back when it comes to giving feedback on auditions.
Taking the same straight-talking approach as head judge Simon, his lines so far have included: "I'd love to go on a night out with you but I never want to hear you sing again" and "Your girlfriend must love you if she thinks you can sing 'cos you really can't."
Not exactly what you want to hear if your chasing popstar success, but for us viewers, we so can't wait to watch!
The X Factor is set to return to screens soon.
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