Bruno Mars is on course to replace Rihanna at the top of the UK singles chart.
The singer's new track 'Grenade' is currently outselling its nearest rival 'Do It Like A Dude' by Jessie J, which has enjoyed a boost after the singer was crowned BBC Sound Of 2011.
Current number one Rihanna's Drake-featuring single 'What's My Name' is at number three, according to the Official Charts Company.
But in the album chart, Rihanna is likely to retain the number one position with 'Loud'.
Plan B's 'The Defamation Of Strictland Banks' is also a non-mover at number two, while Sky 1’s Must Be The Music winner Emma’s Imagination is set to debut at number three.
British Sea Power are expected to chart within the top-20 with new album 'Valhalla Dancehall'.
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