LOS ANGELES: Former Spice Girls star Victoria Beckham had to choose her words carefully when she sat in as a guest judge for American Idol auditions in Boston, Massachusetts and Denver, Colorado - because she didn't want to upset the less talented wannabes.

The Brit was the first celebrity to step up to take over Paula Abdul's vacant chair when the Straight Up singer quit the show just before the auditions for the hit talent show's ninth season began last summer (09) - and her efforts will be seen for the first time on Tuesday (12Jan10), when the new series debuts in America.

The one-time Posh Spice, who is a self-confessed fan of American Idol, admits judging potential contestants is a tough job.

She says, "I was really, really nervous... I didn't want to trample on anybody's dreams. I'm very much a positive person and I believe in positive energy.

"I can find something nice to say about most people. Even if they're completely useless they may have a nice pair of shoes on.