Carrie Underwood will sing the opening theme of NBC's Sunday Night Football for a ninth straight year in 2021, but it hasn't been easy for her or the network. Easily forgotten are the three years she riffed on a Miranda Lambert song in place of "Waiting All Day for Sunday Night."

Then, there was that year she wrote an original introduction anthem that ended up getting her and the network sued for copyright infringement.

Here's a fun fact: Underwood is the third of four artists to perform a football-centric remake of Joan Jett's "I Hate Myself for Loving You" (five if you count Jett herself, who joined Underwood for one memorable year in 2019). Perhaps there's a lot you didn't know or just plain forgot about Underwood's time as NBC's favorite country singer. We got you:

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While "Waiting All Day for Sunday" night has been a football staple for more than 15 (interrupted) years, it might not be the most commercially successful Carrie Underwood song the network has used. That honor goes to Underwood and Ludacris' collaboration of "The Champion," written for Super Bowl 52 on NBC and performed during most of her concerts in the years that have followed. It's a Platinum single that was never sent to radio, but is undeniably among her best songs to make an album (Cry Pretty, from 2018).

About seven months later, "Game On" would debut as the new Sunday Night Football theme song. This Underwood original was used for just one season before becoming the center of a lawsuit in the summer of 2019. Heidi Merrill claimed she pitched a song called "Game On" to Underwood's producer in 2017, and even uploaded her version to YouTube. The lawsuit included nine defendants, Underwood, the NFL and NBC among them. However, it was dropped that fall.

As for the Lambert song that Underwood used? This is the most curious of decisions, as it really didn't benefit the one-time American Idol winner any and had no natural connection to football. In 2014, Lambert and Underwood recorded "Somethin' Bad" together for Lambert's Platinum album. The song would become a Top 10 hit, but ended its radio run before being used to make "Oh, Sunday Night" in 2016. It lasted two seasons.

In each case, NFL players and NBC announcers made cameo appearances in the video element of the Sunday Night Football introduction. It's been filmed in various places through the years, including the Atlanta Falcons stadium in 2019. Watch the video above to learn who the other pop and country stars to sing "Waiting All Day for Sunday Night" were. We bet you remember at least one of them.

Underwood's new opening video will debut ahead of the Sept. 12 Sunday Night Football game between the Chicago Bears and the Los Angeles Rams.

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