The singer's latest hit 'Troublemaker' has retained its position at number one on the midweek chart, while Bruno Mars's 'Locked Out Of Heaven' vaults back up to two.
Rihanna's 'Diamonds' climbs seven places to three, Labrinth stays put at four with 'Beneath Your Beautiful' and Robbie Williams is at five with 'Candy'.
Ke$ha starts at 11 with her new single 'Die Young', Girls Aloud fall to 14 with 'Something New' and Little Mix are at 15 with 'DNA'.
Ladywell Primary School's version of Adolphe Adam's carol 'O Holy Night' moves up to 23, while Athlete's 'Wires' re-enters at 26 following Rylan Clark's rendition of the classic during the X Factor sing-off on Sunday (November 25).
Further down, Taylor Swift begins to gain ground with her new single 'I Knew You Were Trouble', which is up to 28, and The Pogues' festive classic 'Fairytale Of New York' re-enters at 38.
Over on the albums tally, Olly Murs looks set to claim his second UK number one with Right Place Right Time.
One Direction follow at two with Take Me Home, Rihanna slips to three with Unapologetic, and Girl Aloud's new retrospective Ten starts at four.
Elsewhere, Alicia Keys is at 14 with Girl On Fire, McFly are at 15 with Memory Lane and Katherine Jenkins lands at 18 with This Is Christmas.
Further down, Il Divo are at 19 with their Greatest Hits collection, while Kelly Clarkson enters at 25 with The Greatest Hits - Chapter One.
Watch the music video for Olly Murs's 'Troublemaker' below: