(CNN) Carrie Underwood, the NFL and NBC have been hit with a lawsuit that accuses them of plagiarizing the "Sunday Night Football" theme song.

Singer Heidi Merrill and three songwriting collaborators filed the lawsuit Wednesday in federal court in Manhattan, claiming she created a song in 2016 called "Game On" and pitched it to Underwood's producer, Mark Bright, who passed on it.

Merrill alleges that Underwood's song of the same name, "Game On," which was played during the opening of "Sunday Night Football" in 2018, is a direct copyright violation of the song she sent over to the country superstar's team a year earlier.

"This is a blatant attempt by a celebrity singer to rip off other artists' work, and it won't be tolerated," Merrill's attorney, Sam P. Israel, said in a statement to CNN. "It's indefensible to steal music created by hard-working songwriters and then broadcast that theft on national television."

A representative for NBC Sports said the network doesn't comment on pending litigation.

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