Image Credit: Michael Becker/FoxKara DioGuardi will not return for American Idol‘s 10th season, Fox announced in a press release this evening. The word arrived via email at 8:11 p.m. ET on the Friday before the Labor Day weekend, the media-cycle equivalent of attempting to chop down a tree in the forest when no one is there to hear it fall.

“I felt like I won the lottery when I joined American Idol two years ago, but I feel like now is the best time to leave Idol,” said DioGuardi, in a statement released by Fox. “I am very proud to have been associated with American Idol — it has truly been an amazing experience. I am grateful to FOX, FremantleMedia and 19 Entertainment, as well as the cast, crew and contestants, for all they have given to me. I look forward to my next challenge, and want to thank everyone who has supported me. All the best to everyone on Season 10!”

Over the last several weeks, speculation has swirled that DioGuardi, who joined the reality singing competition in its eighth season in the unpopular position of “fourth judge,” would not return to her chair when the ratings juggernaut comes back in January 2011. Returning executive producer Nigel Lythgoe had gone on the record saying he favored a return to a three-person judges’ panel, and as sources close to the show have repeatedly told Entertainment Weekly, Idol has been working to lock down returning judge Randy Jackson, plus newcomers Jennifer Lopez and Steven Tyler, before season 10 callbacks begin in the middle of September. DioGuardi’s name was rarely mentioned as a contender for a rebooted Idol panel, the first without founding judge Simon Cowell, despite the fact that she showed considerable improvement in her on-air performance between the show’s eighth and ninth seasons. In fact, DioGuardi’s father said in an interview last month that his daughter had heard her job was at risk only via media reports.

Fox’s release contained statements from a number of execs close to the show. They read as follows:

“Kara was a great addition to our Idol family. I’ve been fortunate to get to know her well, and have always been amazed by her eye for talent and her commitment to developing and mentoring artists. She will be missed, and we wish her continued success.” –Mike Darnell, President of Alternative Entertainment, Fox Broadcasting Company

“Kara is one of the world’s best songwriters. She has been passionate and committed to Idol over the last two seasons. I will miss having her on the show, but I look forward to working with her in music for many years to come.” –Simon Fuller, American Idol creator and executive producer

“As one of the most proclaimed songwriters in the U.S., Kara brought a wealth of experience and a unique perspective to American Idol. We are very grateful for the time she spent on the show, and we wish her nothing but the best in all her future endeavors.” — Cecile Frot-Coutaz, Idol executive producer

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