Simon Cowell needed six hours of emergency surgery after accidentally breaking his back after falling off his bike on Sunday. 

It was an accident that could have left him paralyzed.

A close friend of the "America's Got Talent" judge told The Mirror UK that the Simon Cowell's injury was very serious, narrowly missed breaking his spinal cord by a centimeter, which would have forbidden him to walk ever again. 

"They had to put a metal rod in his back and fix a number of things. He is recovering in hospital now and we expect him to be there for a few days."

The source added that it's still too early to say when he'll be back to his hosting duties on the hit talent show. 

"America's Got Talent" has started filming again, but Simon Cowell's chair has been left empty as he recovers.

Co-judges Sofia Vergara and Heidi Klum have posted their tributes to Cowell, joined by Howie Mandel, pointing to an empty seat. 

While it's uncertain when Simon Cowell will be back on the show, here are some possible temporary replacements for the TV personality to keep AGT going.

Harry Styles
(Photo : Photo by Arturo Holmes/Getty Images)

Harry Styles

Joining a talent competition at a young age, Harry Styles know how it must have all felt from beginning to end. 

With Styles' chart positions obviously showing he is the biggest solo star from One Direction, ratings of the "America's Got Talent" will surely be a winner. 

Lea Salonga
(Photo : Photo by Dia Dipasupil/Getty Images)

Lea Salonga

Though Tony award-winning star Lea Salonga joined "The Voice Philippines" as a judge-coach, her talent and years of experience in the entertainment industry will surely make her a credible judge for AGT. 

Jackie Chan
(Photo : Photo by Juergen Schwarz/Getty Images)

Jackie Chan

If "America's Got Talent" is all for diversity, then they must add Jackie Chan to their list of judges. 

In 2019, he gave a "World's Got Talent" star a signed copy of his book "never give up," and it would be nice to watch something heart-warming like that on "America's Got Talent."

Sure, he is known for his martial arts skills and action movies, but it would be nice for him to have something different to his resumé - a "Talent Judge."

Chance the Rapper
(Photo : Photo by Emma McIntyre/Getty Image)

Chance the Rapper

In 2018, Chance the Rapper became a judge to "Rhythm + Flow," but AGT will need someone like Chance as a judge. 

He is the most talented rapper of his generation and a pioneer in the industry, who was also the first unsigned artist to appear on "Saturday Night Live." 

Adele
(Photo : Photo by Gareth Cattermole/Getty Images)

Adele

Adele, a spinto mezzo-soprano, is a brilliant singer. even though she has no album yet this year, she is still rolling in the success of her album that came out in 2015. 

She's trending everyday recently because of her dramatic weight-loss and if people saw her every week, ratings for the show would surely increase. 

Beyonce
(Photo : Photo by Gareth Cattermole/Getty Images for Disney)

Beyonce 

Though it is a long shot for Beyonce Knowles-Carter to be a judge on "America's Got Talent," who wouldn't want to be judged by the Queen B herself? 

She didn't just succeed in 2016 with her "Lemonade" album, she put her stamp on history. 

She's about to do it again on "Black Is King," her new visual album. Each time she releases something, it's always a hit and it would've been nice if Beyoncé became a talent judge and shared her secrets to becoming successful.

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