The 'American Music Awards' happened last night and one performance stood out far more than any other.

Psy closed out the show with 'Gangnam Style'...but before it was over, it turned into a DUET...when MC Hammer hit the stage and the song turned into a mash-up of "Gangnam" and 'Too Legit to Quit'!

Here's video:

MC Hammer is 50 years-old and can still dance!