'Start Without You' landed straight in at number one, the third time that the series five winner has achieved this feat, bumping Murs's track 'Please Dont Let Me Go' down to four.
Irish group The Script squeeze into the top five with their latest single 'For The First Time', while McFly's comeback single 'Party Girl' lands just behind them at six, becoming the boyband's fifteenth Top 10 release in six years.
Must Be The Music semi-finalist Emma's Imagination manages to replicate the success of her fellow contestants Pepper & Piano, as single 'This Day' breaks into the Top 10 off the back of her appearance on the show.
Elsewhere in the chart, former number ones 'We No Speak Americano' by Yolanda Be Cool & D Cup and 'Green Light' by Roll Deep slip just out of the Top 10, settling in at 11 and 13 respectively.
Meanwhile, Strictly Come Dancing judge Alesha Dixon returns to the charts as well as television screens, as new single 'Drummer Boy' debuts at 15.
The popularity of X Factor hopeful Cher Lloyd's performance of 'Turn My Swag On' sees the little-known version of the song by Greg Street enter the chart at 17, although both the Soulja Boy original and the Keri Hilson cover that Lloyd actually sung are absent.
The Top 10 in full:
1. (-) Alexandra Burke ft. Laza Morgan: 'Start Without You'
2. (2) Katy Perry: 'Teenage Dream'
3. (3) Taio Cruz: 'Dynamite
4. (1) Olly Murs: 'Please Don't Let Me Go'
5. (-) The Script: 'For The First Time'
6. (-) McFly: 'Party Girl'
7. (4) Eminem & Rihanna: 'Love The Way You Lie'
8. (8) Katy B: 'Katy On A Mission'
9. (5) Flo Rida ft. David Guetta: 'Club Can't Handle Me'
10. (-) Emma's Imagination: 'This Day'
Source: Official Charts Company
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