Some songs just shouldn't be covered - especially if it means putting a tacky beat on top of it and consequently stripping it of all that made the original so good.

Try telling that to John Legend, though. He joined young Norwegian producer Kygo on stage at The Greek Theatre in Los Angeles the other night to perform the latter's reworking of Marvin Gaye's soul classic.

It's not that Legend's vocals are bad, but the dancey pan pipes (!) do absolutely nothing for the song. You'd hear a better version at your local karaoke night.

Harsh? Don't just take our word for it - watch it below: