X Factor USA stars Alex & Sierra are already wowing the show's judges and viewers with their stunning renditions but now the musical duo have stormed the iTunes chart.
Following their best night yet on Wednesday's show, the duo's week just keeps getting better as their rendition of 'Say Something' shoots to the top of the iTunes top 400 singles chart.
The gorgeous track first landed at number two in the early hours of this morning, just behind Pitbull's 'Timber' before jumping up to number one a couple of hours later.
22-year-old Sierra was blown away by the news as she tweeted "WE'RE NUMBER ONE ON ITUNES I'M DONE I'M DONE STICK A FORK IN ME I'M DONE."
Simon Cowell also added his praise as he simply posted: "Alex and Sierra number one on iTunes. Incredible"
You can say that again Si!
The couple won the night's biggest plaudits from judges Cowell, Kelly Rowland, Demi Lovato and Paulina Rubio last night after two sensational performances.
Alex & Sierra are number one on iTunes (WENN)
The pair firstly took on a unique twist on Destiny's Child smash 'Say My Name' - of course winning the approval of former member Rowland.
“I must admit I was not ready for that. It was a couple of moments in there where I was like, ‘Is this my song?’” she commented afterwards. “I was really shocked. But you guys really actually pulled that off.”
Their popularity was sealed with a performance of A Great Big World and Christina Aguilera's current smash 'Say Something', a performance that Lovato labelled "so beautiful".
Piling on the praise, Cowell said: "This, for me, wasn’t just the best performance of the night, cause it was. In so many ways, this is my favorite performance of the entire season from anyone.
"That wasn’t just a performance, that was a record. And I will be downloading that on iTunes in about 10 minutes... It was outstanding, it was beautiful, sincere, fantastic."
Looks like Simon's downloading helped propel the track to the top spot!