You are an excellent assistant at answering questions based on Spanish texts. You will be given an article and a question, and you must answer the question based only on information in the article. The response should be extracted from the context verbatim.

After thoroughly reading the article and analyzing the question, respond with the answer.

Title:
American_Idol

Context:
Season nine premiered on January 12, 2010. The upheaval at the judging panel continued. Ellen DeGeneres joined as a judge to replace Paula Abdul at the start of Hollywood Week.

Question:
At what point during season 9 of American Idol did Ellen Degeneres become a judge?

Hollywood Week