Judge Rita Ora was booed by the crowd following her decision to unseat contestant Karen Mav for Kiera Weathers during The X Factor's Six Chair Challenge.
In the dramatic episode, 23-year-old Mav impressed with I'd Rather Go Blind by Etta James, but 18-year-old Weathers blew the panel away with Whitney Houston classic I Will Always Love You and was rewarded with a seat by Girls mentor Ora.
The audience did not like the decision and turned on the Poison singer as she left the panel to comfort a distressed Mav, who had burst into tears.
"I'm so sorry," Ora told her as Wembley's SSE Arena erupted into chants of "Bring her back!"
In this controversial part of boot camp, each judge cuts their category down to six acts to take to Judges' Houses by granting one a seat on stage if they are considered good enough.
When all six chairs are taken, if a better choice comes along, a seated contestant can be swapped out of their chair - and possibly out of the ITV competition.
That was Monica Michael's fate in 2014, but the Londoner has made it through to the next round this year alongside 17-year-old Louisa Johnson and 21-year-old Chloe Paige, who took a risk singing Amazing Grace a capella.
In a first for The X Factor, the public had their say as to the categories each judge would be mentoring. BBC Radio 1's Nick Grimshaw is in charge of the Boys, while Cheryl Fernandez-Versini heads up the Groups.
TV mogul Simon Cowell threw a strop and swore out loud after being handed the Overs. "Oh, f***! Are you winding me up?" he said, before asking if the right name was called out.
Tensions erupted into a spat between Cowell and the Girls mentor Ora following Katie Coleman's rendition of Christina Aguilera's The Voice Within.
"You were better the first time, but if it was me, I would give you a chair," the X Factor supremo told the 21-year-old. The crowd believed he liked the performance and cheered. However, he added: "Not one of those. I'd give you a chair at home. I don't think it was good enough."
Ora fired back: "That was just rude. Simon, if you would just like to mind your own business and wait until your category comes up." However, she decided not to give the Darlington contestant a chair.
Another misfire on the night was 23-year-old Kelly Mai Webb, who was woefully off-key with her version of Patti Smith's Because The Night. The Blackpool hopeful's X Factor dream came to a swift end.
Two former favourites also became casualties as the gruelling challenge saw 17-year-old Charli Beard lose her seat to retail assistant Havva Rebke and Essex's Lucy Duffield had to make way for 25-year-old dental assistant Lauren Murray.
The X Factor airs on ITV on Sunday October 11 at 7pm.