It's not unusual for an artist to jump on stage at a concert for an impromptu duet.  Brad Paisley joined Carrie Underwood for 'Remind Me' during her show in Nashville last night. 

I'm sure it was planned in advance, but to the audience it looked like Brad surprised Carrie for the song.  They were in Nashville after all; so I'm sure it wouldn't have been too difficult to set up the duet ahead of time.  Plus, the two are spending a lot of time together rehearsing to host the CMA Awards again this year.  They've even taped three hilarious spots for the show.

I've since been corrected. The duet wasn't planned after all.  After posting the story,a fan set me straight on Twitter.

Twitter

Watch the two on stage in Nashville last night.