The South Korean star was in the middle of a performance of worldwide hit 'Gangnam Style' when the audience began to boo - very loudly.
We're not sure if they were booing because they just weren't feeling it or to prove a point, but word on the grapevine is it was a joint effort by the audience as the performance had nothing to do with football.
We'd have just walked off stage. Psy's a lot more composed than we are, though, and said a jolly "Thank you!" amidst all the boos.
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