Funny man Simon is no stranger to pushing people's buttons and while his usual victim is his fellow X Factor judge Cheryl Fernandez-Versini, Sarah-Jane has revealed it is now her this time round.
Speaking to the Mail Online, Sarah-Jane said she was very similar to the Girls Aloud singer as it "doesn't take much to wind her up" and Simon was quick to figure that out.
Sarah-Jane said: "That's the reason [Simon] goes for [Cheryl] too - it doesn't take much to get a reaction... He loves to joke around."
The Radio 1Xtra DJ revealed that if she isn't getting teased about her boyfriend - Simon tells her she is punching above her weight and her boyfriend Ross is too good looking for her - there's always something else to be picked on.
Recalling her funniest encounter with her boss, Sarah-Jane said Simon had joked his dogs, Squiddly and Diddly, were more popular than she was.
To test his theory, the 54-year-old took to Twitter posting a shout out for Sarah-Jane, then immediately posting a photo of his pet pooches after.
Sarah-Jane told the Mail Online: "[Simon] said we'd judge how popular we both were by how many responses they got... After a couple of hours when I next bumped into him, he was like, 'So my dogs got this many thousands of favourites and re-tweets, and you got just this many, hmmmmm'."
But the brunette beauty did admit that luckily she gets to tease Simon back, thanks to his "great sense of humour".
Let's hope she gives just as good as she gets!
Sarah-Jane was announced as the new host of The Xtra Factor to replace Caroline Flack who quit the show after three years.
TV star Caroline has now, interestingly, announced she will be taking part in BBC's Strictly Come Dancing - the X Factor's rival show.
The X Factor is back this Saturday 30 August on ITV.
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