The Bajan star's Calvin Harris team-up outperformed midweek chart-toppers The Wanted and their sixth single 'Lightning' to recapture pole position.
Third place this Sunday goes to Charlene Soraia's cover of 'Wherever You Will Go', which climbs from seven following its use in a popular TV advert and a performance by X Factor contestant Sophie Habibis on last week's show.
'Moves Like Jagger' by Maroon 5 and Christina Aguilera, which has finished runner-up on the chart for the last seven weeks, is down to four, as the original American Idol Kelly Clarkson scores her seventh UK Top 10 with 'Mr Know It All' at six.
New York-based singer Lana Del Rey makes her chart debut at nine with 'Video Games', David Guetta and Usher climb to ten from last week's 16 with 'Without You' and Sean Paul's new Alexis Jordan collaboration 'Got 2 Luv U' just misses the top-sellers at 11.
Former chart-topper Sak Noel and Ed Sheeran fall five together to 13 and 14 with 'Loca People' and 'The A Team', while The Calling return to the Top 20 after climbing nine to 16 with the original 'Wherever You Will Go', which peaked at three on the UK chart in 2002.
Ed Sheeran makes a second appearance at 18 with 'Lego House', which is up 13 places this week, and James Morrison completes the upper half of the rankings with 'I Won't Let You Go', down five to 20.
Elsewhere, Justin Bieber is a new entry at 21 with his Christmas-themed track 'Mistletoe', while Katy Perry is straight in at 22 with 'The One That Got Away'. Finally, Noel Gallagher's High Flying Birds re-enter the Top 40 with 'AKA...What A Life!' following the former Oasis star's album chart success.
The Top 10 in full:
1. (1) Rihanna ft. Calvin Harris: 'We Found Love'
2. (-) The Wanted: 'Lightning'
3. (7) Charlene Soraia: 'Wherever You Will Go'
4. (2) Maroon 5 ft. Christina Aguilera: 'Moves Like Jagger'
5. (3) Gym Class Heroes ft. Adam Levine: 'Stereo Hearts'
6. (-) Kelly Clarkson: 'Mr Know It All'
7. (4) Christina Perri: 'Jar Of Hearts'
8. (5) LMFAO: 'Sexy And I Know It'
9. (-) Lana Del Rey: 'Video Games'
10. (16) David Guetta ft. Usher: 'Without You'
Source: Official Charts Company
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