UPDATE:Simon Cowell unlikely to return to X Factor tonight after further health worries

Simon Cowell is unlikely to be in the judging panel in tonight's The X Factor, after doctors concerns that he is not well enough.

The telly mogul missed the first live show of The X Factor 2017 on Saturday after he fainted and fell down his stairs on Friday morning.

He said he was 'feeling okay to photographers outside his home and told them, "I fainted and fell down the stairs. I've got a bit of concussion. I feel better now.'

"I will be back but I don’t know about tomorrow. But I’m feeling OK.

It is thought that Alesha Dixon will step in as a guest judge, if Simon is not deemed healthy enough for the grueling live shows.

A source told The Mirror Online, 'The decision is not 100% yet but it's very likely he'll sit out this one on doctor's advice.

"Alesha Dixon is ready to step in as a substitute judge if necessary.

Simon had an array of brain, neck and spine scans after falling in his home in West London.

A source told The Sun, "It was a truly terrifying accident and could have been a lot worse.

"Simon had woken up and wasn’t feeling right. He was dizzy so went downstairs to fetch some warm milk.

"He fainted when he was climbing back up the stairs to the first floor. His security team heard a loud thump and knew he’d gone down.

"They immediately called emergency services and an ambulance rushed to the house.

NOW READ: Taylor Swift has a doppelgänger and it's 20-year-old student Laura Cadman...

Like, she looks EXACTLY like T-Swizzle!