From left, Randy Jackson, Paula Abdul, and Simon Cowell speak at the "American Idol" farewell season finale at the Dolby Theatre on Thursday, April 7, 2016, in Los Angeles. (Photo by Matt Sayles/Invision/AP)
On Wednesday's 'Idol,' Renae invoked Clarkson's name as the inaugural winner and good-naturedly vowed that "a woman started it and a woman's goin' finish it."
'American Idol,' once a ratings powerhouse that influenced TV and music, had suffered steady audience erosion before Fox decided it would end this season.
Series executive producer Nigel Lythgoe promised the finale would celebrate its large ranks of contestants, not big-name guests as in previous years, and he stuck to that pledge.
The show opened with a harmonizing chorus of white-clad winners and contenders including Scotty McCreery, Taylor Hicks and Diana DeGarmo.
Other familiar faces from years past popped up in solos and group numbers, including Carrie Underwood, Jennifer Hudson, David Cook, Fantasia, Ruben Studdard, Jordin Sparks and Kimberley Locke.
Judges got in on the act as well. Keith Urban and Underwood dueted, while Harry Connick Jr. saluted a music center in New Orleans' Katrina battered-Ninth Ward by inviting a young student, Marley Fletcher, to join him on 'It's a Wonderful World.' Jennifer Lopez performed her new single.
Clarkson, who's expecting her second child soon, appeared in a pre-taped performance.
There was a brief nod to nostalgia, with clips from past auditions presided over by original judges Simon Cowell, Paula Abdul and Randy Jackson. Abdul and Jackson showed up to salute Seacrest for his longevity, with Cowell strolling on stage belatedly to steal the spotlight.
"I'm feeling quite emotional now," said the usually acerbic Cowell.