The BBC Sound of 2011 winner had finished in second place to Chipmunk and Chris Brown's 'Champion' when the chart update was announced on Wednesday, but later retained the lead by a margin of 5% to achieve a second Sunday in pole position. Both tracks shifted over 90,000 copies this week.
Meanwhile, Lady GaGa's long-awaited comeback track 'Born This Way' soared into third after clocking up 60,000 sales in just 34 hours of release. The song had originally been due to come out today, but was unveiled on Friday afternoon at the 'Alejandro' singer's request.
Outside the top five, 'Champion' guest vocalist Chris Brown's comeback continues to gain momentum as 'Yeah 3x' climbs three places to this week's six, while former number one 'We R Who We R' by Ke$ha slips behind him at seven from its previous position of three.
Despite holding steady at the top of the chart, Jessie J sees her debut single 'Do It Like A Dude' fall back out of the top ten to 12, one place behind the artist it was originally intended for, Rihanna, who advances nine spots with the controversial 'S&M'.
Other fallers this week include Chase & Status with 'Blind Faith', down four to 14, Tinie Tempah and Ellie Goulding's 'Wonderman', which is at 18 from last week's 14, and 'Traktor' by Wretch 32, which crashes eight positions to 20.
The top ten in full:
1. (1) Jessie J ft. B.o.B: 'Price Tag'
2. (-) Chipmunk ft. Chris Brown: 'Champion'
3. (-) Lady GaGa: 'Born This Way'
4. (2) Bruno Mars: 'Grenade'
5. (4) Adele: 'Rolling In The Deep'
6. (9) Chris Brown: 'Yeah 3x'
7. (3) Ke$ha: 'We R Who We R'
8. (8) Taio Cruz ft. Kylie Minogue: 'Higher'
9. (5) Enrique Iglesias ft. Ludacris: 'Tonight (I'm Loving You)'
10. (6) Diddy-Dirty Money ft. Skylar Grey: 'Coming Home'
Source: Official Charts Company
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