This started from a reference on "Community" where my character Abed mentioned that he was an extra on the set of a show and that he was a fan of "Cougar Town".

Two of our writers, Neil Goldman and Garrett Donovan, also worked on "Scrubs" with Bill Lawrence who was the creator of "Cougar Town". One day I got a text from one of them asking me if I would like to appear on "Cougar Town" and I said, "Sure, why not?"

They told me to be a background actor during a scene with Busy Philipps and I was the worst background actor of all time. I was staring at the camera and very engaged in their scene.

http://ew.com/tv/2017/09/21/danny-pudi-community-movie/