NEW YORK -- A songwriting team sued country singer Carrie Underwood, the NFL and NBC Wednesday, saying they stole a song and "slightly modified" it to introduce "Sunday Night Football" to viewers last season.

The lawsuit in Manhattan federal court noted that Underwood's "Game On" even carried the same title as the song singer Heidi Merrill of Newport Beach, California, put on an internet music video two years ago.

The lawsuit sought unspecified damages, saying the copyright was violated on the song that had been pitched to Underwood's representatives in 2017.

The NFL and NBCUniversal Media LLC declined comment. Carrie Underwood's representatives did not immediately comment.

The plaintiffs are a songwriting team consisting of four individuals, including Merrill, from California, Tennessee and Sweden.

The lawsuit said Merrill assembled the group to create the song in 2016 as a follow to her Nebraska-themed football anthem "Cornhusker Strong."

It said they marketed the song, aiming to get it licensed for use in television broadcasts of sporting events.

Merrill pitched the song to Underwood's producer in August 2017 during a conference in Nashville, Tennessee, where Underwood lives, the lawsuit said.

It said the producer referred Merrill to his assistant, who told her in an email in October 2017: "I'm sorry, we're going to have to pass."

The lawsuit claimed that the song that introduced 17 NFL Sunday night games through the season beginning in September 2018 "is substantially -- even strikingly -- similar, if not identical," to the song Underwood's team had rejected.