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Remember When Taylor Swift and Miley Cyrus Collaborated at the 2009 Grammys?

Swift and Cyrus shared the stage at the 51st Grammy Awards on Feb. 8, 2009.

Taylor Swift and Miley Cyrus go into Sunday's (Feb. 4) Grammy Awards with six nominations in the same categories. Both artists are up for Record of the Year, Album of the Year, Song of the Year (as songwriters) and Best Pop Vocal Album. Although Swift and Cyrus, now 34 and 31, will go head-to-head at this year's ceremony, it wasn't too long ago that they took the Grammys' stage together.

That unforgettable moment happened at the 51st Grammy Awards on Feb. 8, 2009. The two were mere teenagers (Swift 19, Cyrus 16) when they shared music's biggest stage and blew fans away with their duet rendition of Swift's "Fifteen." A look back at the performance shows the singers sitting on a stage in the middle of the arena as they sing the teenage anthem from Swift's Fearless album. Swift — with her curly locks styled in a messy bun — plays the acoustic guitar as she sings the first verses solo. Cyrus then brings her signature voice to the chorus.

The two trade lines and sing together during the rendition, looking like they'd lived every word about awkward teenage romances and making new friends. At the end of the song, Swift and Cyrus grab each other's hand and laugh giddily.

Swift was in the middle of her Fearless era at the 51st Grammys. At the time of this performance, "Fifteen" was still just an album cut, and her single "White Horse" was climbing the charts. "Fifteen" wouldn't be officially released to radio until August 2009, following "You Belong With Me."

Cyrus was still starring in her TV series "Hannah Montana" in 2009, and she'd seen success in her  music career with songs like "See You Again" and "7 Things." She was about to step into more fame, however, with the release of multi-platinum hits "The Climb" and "Party in the U.S.A." later that year.

Neither Cyrus nor Swift are on the performance list for this year, but the Grammys will feature performances from Luke Combs (reportedly featuring Tracy Chapman), Billy Joel, Joni Mitchell and many more.

The Grammy Awards air live from Crypto.com Arena at 8 p.m. ET on CBS.

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