‘Celebrity Apprentice’s’ Clay Aiken Says Donald Trump Scarier Than Simon Cowell

American Idol Season Two runner up Clay Aiken found it easier to face notoriously crabby former Idol judge Simon Cowell than Donald Trump, whom he takes on in the new season of NBC’s Celebrity Apprentice.

Aiken told Today.com, “Being in front of Trump is more intimidating than (being in front of Cowell). That’s because you realize his success is real outside of TV. Whereas with Cowell, I don’t deny him his value – but singing is not his expertise.

“I expected meanness from Simon, because I felt Simon’s job was to be rough and brutal, and therefore it didn’t matter as much what he said to me.”

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Aiken’s comments, said years after he competed on the second season of American Idol, are interesting considering that Cowell told Aiken in 2006 that he’d given the worst Idol performance ever for his rendition of “Grease.”

Aiken explained that Trump was more intimidating because he is knowledgeable in fields Aiken knows little about, “Singing I can do, and if Simon didn’t like it then I wouldn’t be like, ‘I can’t sing!’ With Trump, it’s not my expertise, and it is his, and so therefore I have a little more respect for him because I realize I’ve got to work harder.”

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Aiken is part of Celebrity Apprentice‘s largest cast to date, which includes Arsenio Hall, Tia Carrere, Debbie Gibson, Adam Carolla and Star Trek‘s George Takei.

Trump told The Hollywood Reporter of the show’s fifth cycle, “It’s hard to top the last few seasons but we think we’ve done it.”

The 15-episode season kicks off Feb. 12.