During The Voice's Monday night episode (May 17), Season 20's Top 9 finalists performed live as they vied for viewers' votes. But that wasn't all the show had in store: It also featured a blast from The Voice's past in the form of Season 19 finalist Ian Flanigan.

Repping the country genre for Team Blake with performances of songs by the likes of Jamey Johnson and Travis Tritt, Flanigan made it all the way to the finals last season, ultimately ending his time on the show in third place. He impressed not only with his expert country covers but also with his original material. As a Top 5 contestant, he performed a song called "Never Learn," which earned praise from coaches Blake Shelton and John Legend for its impactful lyrics.

On Monday night, Flanigan returned to his old stomping grounds to give a live performance of his new song, "Grow Up," featuring none other than Shelton himself on backing vocals. With a heart-pounding drum beat and the singer's signature vocal rasp, "Grow Up" demonstrated that Flanigan has continued to hone his powerful songwriting style since exiting the show in December of 2020.

"They say we're never gonna grow up / Well, they might be right / 'Cause we're loud, we're alive / And tonight we're raisin' somethin' cold up," Flanigan sings in the chorus of the song, with Shelton providing harmonies. "We thought we would one day / But hey, we ain't / 'Cause one day still ain't showed up / Guess we're never gonna grow up...."

Flanigan just released a studio version of "Grow Up," also featuring Shelton's vocals. The track premiered early in May 2021.

Shelton pulled double duty during Monday night's live performances episode of The Voice, serving as coach to two remaining contestants on Season 20 -- Jordan Matthew Young and Cam Anthony -- in addition to lending backing vocals and guitarwork to Flanigan's performance.

The Voice airs at 8PM ET on Monday and Tuesday nights on NBC.

 The Voice Stars, Then + Now:

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