LOS ANGELES, California (AP) -- A key "American Idol" producer who's guided the top-rated TV show since its debut is leaving the job as the Fox juggernaut faces the challenge of staying on top in its eighth season.
Nigel Lythgoe is negotiating a joint-venture deal with "American Idol" creator Simon Fuller and 19 Entertainment, the company announced Monday.
The smiling, blond-haired Englishman, who could often be spotted on-camera sitting behind the "American Idol" judges' row, is familiar to viewers on "So You Think You Can Dance?", which he produces and helps judge.
"I will step back from my day-to-day producing work on 'American Idol' and will be devoting my time" to the new enterprise, Lythgoe said in a statement.
The change comes as "American Idol" jockeys to keep its hold on the No. 1 ratings spot, a rare feat for an aging show, and after last season's small ratings downturn and an unsettling audience shift.
The series averaged 28.4 million weekly viewers last season compared to the 30.8 million who watched during its highest-rated year, 2005-06.
Viewership for the May finale with winner David Cook and runner-up David Archuleta was the second-highest for the show in five years, but dropped slightly from last year among 18-to-49-year-old viewers -- an indication that the "American Idol" audience is aging.
Fox congratulated Lythgoe on his new venture but acknowledged it was "disappointed" that he would not be continuing as executive producer.
"He is an extraordinarily talented producer whose creative contributions to the No. 1 show on television have been immeasurable," the network said in a statement.
It was unclear whether Lythgoe will continue to have a hand in "American Idol." His fellow executive producer, Ken Warwick, also has worked on the show from the beginning.
Asked what roles Lythgoe and Warwick might have with the show when it returns next January, 19 Entertainment spokesman Eric Green said the producers for next season have yet to be decided.
National auditions for the singing contest's new season are under way.
In a statement, Fuller called Lythgoe "the best producer I have ever worked with" and noted they have collaborated for more than 10 years. Fuller heads 19 Entertainment, which produces "American Idol" with FremantleMedia North America.
TV, film and stage projects all will be on the table for Fuller and Lythgoe's new enterprise, Green said.
The two created the "So You Think You Can Dance?" contest series, which airs on Fox.