Kelly Clarkson graced the stage of American Idol for the very last episode ever, returning to the stage where it all began for her ... only, she wasn't actually there.

The original idol was announced as one of the performers on the special two-hour finale of the ever-popular reality television singing competition, which revolutionized television when it first graced the airwaves 15 years ago, inspiring a host of imitators that include Nashville Star and The Voice.

But as Ryan Seacrest explained Thursday night, Clarkson couldn't be on hand for the live finale because she is slated to give birth to her second child soon. Instead, she pre-taped a very special medley during a recent visit to the Idol stage, so that she could send the show that launched her career off in style.

Clarkson won the first season of Idol, and in the 15 years since she has become one of the biggest superstars in contemporary music, including several forays into country music. She ran through a career-spanning medley in Thursday night's pre-taped performance, including "Miss Independence," "Breakaway," "Since You've Been Gone," "Because of You," "Stronger," "My Life Would Suck Without You," "Don't You Wanna Stay," "Heartbeat Song," "Invincible" and "A Moment Like This," the song that she released as her first single and that she debuted on the show when she won her career-making victory over Justin Guarini at the end of the show's first season.

Clarkson was just one of the many Idol alumni who returned for the finale, including Carrie Underwood, whose own career was launched on the Idol stage when she won the show's fourth season.

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