Quite a few major country singers have been discovered over the 15 seasons of American Idol, a fact that was brought home on the series finale on Thursday night (April 7). Scotty McCreery and Lauren Alaina led a group performance from various country singers who launched their careers on Idol during the finale.

Diana DeGarmo started things off and was joined by Skylar Laine for Taylor Swift's "You Belong With Me," which also included Kree Harrison. Bucky Covington led another song with two other past contestants, followed by Alaina and Kellie Pickler, who launched into the Band Perry's "Done."

McCreery emerged from the wings to begin Garth Brooks' "Papa Loved Mama," which featured the entire group backing him up as he took the lead. The entire group also participated in a high-energy performance of "Where the Pavement Ends" to close out the country set, drawing a rousing round of applause from the crowd who assembled to witness the iconic reality television sing program come to an end.

A virtual Who's Who of Idol alumni returned for the series finale, including Carrie Underwood, who won Season 4 and sang a duet with Keith Urban on "Stop Draggin' My Heart Around" on Thursday night. Kelly Clarkson, who won the show's inaugural season, also appeared in a pre-taped performance. Since she was unable to attend due to the upcoming birth of her second child, she pre-taped a special career-spanning medley of her hits to bid a fond farewell to the show that made her into a global superstar.

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