How else can I delete a purchased song?

I have this song that was a free download on my IPhone 4, no matter what I do, I can't get this thing off my phone! I can't stand this song. I've deleted it in my Itunes, but it wont come off my phone. (swiping on the song does nothing!) I've added and changed my playlist numerous times, updated my phone, restored my backup files, And yet it still remains!