Popstar Katy Perry promises a larger-than-life pre-game performance ahead of AFL grand final

American popstar Katy Perry has promised a larger-than-life performance at the AFL grand final on Saturday. The singer behind hits like "Roar" and "Firework" headlines the pre-game entertainment ahead of the decider between Brisbane and Sydney at the MCG. Despite embracing the game and even handballing a Sherrin, Perry was decidedly cagey on which team she's backing.