Nick is a Bulls fan. Jess is pretending to be a Pistons fan. This is a problem.
Nick can't get over it when Jess likes a basketball team he hates on New Girl. "Basketsball" is the 12th episode of the show's third season.

New Girl Season 3 Episode 12 Quotes

Jess: Nothin' but net!
Coach: Traditionally, that refers to hitting nothing but the inside of the net.

Winston: So...where do you do the marketing?
Schmidt: Oh, Winston. So naive, so sweet. We do the marketing EVERYWHERE!