Sparks' sophomore albumBattlefield was released in July 2009 worldwide and debuted at #7 in the US, three spots higher than her first album. The album's lead single, also titled "Battlefield", peaked in the top 10 on the Billboard Hot 100 and has sold more than a million copies thus far. Sparks has sold about 9 million singles worldwide to date. Sparks' first five singles all peaked in the top 20 on the US Billboard Hot 100, three of them peaking in the top 10. Battlefield's second single, "S.O.S. (Let the Music Play)", was her first song to top the US Billboard Hot Dance Club Play making it her first U.S. number one single.