An agitator

Sean Avery, who plays left wing for the New York Rangers, is what hockey people call an agitator. His job, which seems to have no analogue in sports -or in any line of work, except maybe terrorism- is to annoy opponents so intensely that they cannot resist realiating. He goads foes into losing their focus and, in theory, the game. Every team in the National Hockey League has at least one agitator, but Avery may be the best, or the worst, of the current lot. His peers have voted him, by a wide margin, the most hated player in the league, and the dirtiest.

Nick Paumgarten, The New Yorker. Puckhead.