Simon Cowell's British talent show The X Factor has crowned Matt Cardle its newest winner, and the singer has already topped the UK's Christmas-week singles chart with his cover of Biffy Clyro's "When We Collide." But the show hasn't left the headlines in the UK just yet, thanks to Christina Aguilera and Rihanna, who got a little raunchy for some viewers' taste.
More than 4,000 complaints were sent to the British media regulator Ofcom and X Factor network ITV in the wake of the pop stars' performances, which were broadcast between 7 p.m. and 9 p.m. local time on December 11. An average of 14 million viewers across the UK watched the show.
Aguilera, promoting her debut movie role in Burlesque, sang two tracks from that film, while Rihanna performed "What's My Name," which is currently sitting right behind Cardle's song on the UK singles chart. Both singers also dueted with the finalists.
The Daily Mail led the charge against the show this week, publishing what it deemed the most controversial stills from the broadcast "to show the fury they've caused" because of their pre-9 p.m. airtime. The paper also referred to the routines as "louche" and "very adult."
Watch the performances and judge for yourself -- were they too steamy for the family hour?
Rihanna performs "What's My Name":
Christina Aguilera performs "Express":