"Chelsea Dagger" is a song by Scottish rock band The Fratellis and their second single. It was released on 28 August 2006. It is taken from their debut album Costello Music, which was released in the United Kingdom on 11 September 2006. It is named after Jon Fratelli's wife Heather, a burlesque dancer whose stage name – Chelsea Dagger, a play on Britney Spears – he borrowed for the song. Fratelli described the tune as "a rock 'n' roll gig in an old speakeasy or something like that."
Outside of football, it is best known as the goal song of the National Hockey League's Chicago Blackhawks. The song was first used after owner Rocky Wirtz inherited the team from his father, Bill, and introduced more up-tempo music in an effort to attract younger fans. The song became a sensation during the Blackhawks' first Stanley Cup run in 49 years in 2010. The success of the Blackhawks has led "Chelsea Dagger" to be adopted as a goal song by the University of North Dakota, among others. Blackhawks Executive Producer, Tom O'Grady said, "We aggressively searched for a memorable goal song, then heard "Chelsea Dagger" watching a Celtic match and was immediately struck by the song's quirky and contagious chant..." It wasn't an immediate hit, however. "The first few games playing "Chelsea Dagger", fan responses were pretty tough, but at the same time the Blackhawks started playing very well, piling up the goals and victories and boom... "Chelsea Dagger" was adopted as the teams' anthem and quickly became a huge part of the Blackhawks brand experience." The song is used now by the entire Blackhawks system, as the Rockford IceHogs (AHL) and Indianapolis Fuel (ECHL) clubs, all part of the Blackhawks system, use the song after goals.