Every week day, PopCrush will stage a 'Sound Off' between two new songs, and readers like you will have the chance to vote for the song you like best. Today, Oct. 18, our 'Sound Off' is between two of pop's leading ladies -- Rihanna and Katy Perry.

Rihanna is getting ready to release her new LP 'Talk That Talk' this November, and she recently released the '90s inspired club banger 'We Found Love' as the album's lead single. Katy Perry, on the other hand, has just released the sixth and most likely final single, 'The One That Got Away,' off of her 2010 'Teenage Dream' album. Although the girls are friends in real life, we are matching them up in a head-to-head battle to see which song listeners are feeling the most.

There is one catch, however; if an artist's song wins five days in a row, we will retire that song to give another track the chance to prevail in our 'Sound Off' series. So vote for either Rihanna's 'We Found Love' or Katy Perry's 'The One That Got Away' and we'll let you know who wins the 'Sound Off' tomorrow!

Listen to Rihanna, 'We Found Love'

Listen to Katy Perry, 'The One That Got Away'