The four-piece boyband, who won the ITV show a week ago today, took to the stage at London’s O2 Arena to showcase their debut single.
Dimelo had fans screaming and dancing along, and a recording of the performance has already had upwards of 40,000 views on YouTube.
Yesterday’s Jingle Bell Ball also boasted performances from Dua Lipa, Niall Horan, Sam Smith and Rita Ora among others.
The event continues tonight with appearances from Taylor Swift and Ed Sheeran.
However Ed Sheeran and Beyonce’s Perfect Duet stopped them from recapturing the days when the talent show’s winners would effortlessly glide to the summit.
Yesterday the four-piece boyband confirmed that their new music will be along sooner rather than later; opting out of the usual system that sees X Factor winners waiting until the following autumn.
They told BBC Radio 2’s Graham Norton Show, via Digital Spy: “What we are going to do is the songs that we’ve done on the show previously, we’re going to try and get some studio version of that done.
“Maybe plus another couple of songs and then put those together into a project to release early next year. And then we’re going to start work on the album as well.
“But I think we’ve got an opportunity at the moment and some momentum behind us, and we just want to use it.”
Capital FM’s Jingle Bell Ball continues tonight.