Madonna performed with Psy in New York last night. The "Girl Gone Wild" singer - who is currently on her worldwide MDNA Tour - unveiled the South Korean pop sensation as her special guest at the concert at the city's Madison Square Garden, where they performed a mash-up of her song "Give It To Me" and his cult smash "Gangnam Style." Madonna even performed Psy's "horse" dance - copied by stars including Mel B and Heidi Klum - and at one point crawled between his legs.

The event comes just a week after the 54-year-old star was "rejected" by Lady Gaga when she asked her to sing with her on stage. She told a crowd in Minnesota earlier this month, "I have the best fans in the whole world. So take that, Lady Gaga. You know, I invited her to sing with me on stage but she turned me down. It's OK. I've been rejected before. It's good to build character."