Now that the season finale of “American Idol” is over, the attention turns back to who is going to fill Simon’s seat as the fourth judge.

Replacing Cowell poses a tremendous challenge for 19 and Fox, especially when everyone seems to have an opinion on who should get the job. Another name recently thrown in the ring is that of Madonna.

A source told The Sun: “Simon is going to leave a gaping hole. Not only is he an expert, he’s also a big star in the States.

“Everyone agrees Madge would be great and they want her as a full-time judge. But if that fails they’d at least like her as a mentor.”

Chatting to Oprah Winfery show last week, Simon insisted that his replacement should be someone that “actually knows what they’re talking about”.

“Everyone’s talking about casting a nasty person or getting another Brit,” he explained. “ If we were judging the ice skating Olympics, you wouldn’t have somebody on who’s obnoxious, you’d have somebody who knows the difference between a ten, a nine and an eight. I think, to a point, you kind of have to go back to that.”