American Idol sensation CRYSTAL BOWERSOX has a secret gay past, The ENQUIRER has learned exclusively.

As a wild, pot-smoking and boozing teenager, she had at least three lesbian affairs – and boasted to a girlfriend she was seducing: "I’m a pro at this, baby!"

"Crystal was a free spirit," a friend told The ENQUIRER. "She wasn’t slutty, but if she found someone attractive, whether male or female, she’d give them a chance with her."

The Idol finalist already had an active sex life when she was a 10th grader at Toledo School for the Arts in Ohio.

"It was around New Year’s 2002," disclosed the friend. "Crystal was 16 and she and I were chatting with a pal, a younger boy.

"The conversation got around to our sexual experiences

 "Crystal wasn’t at all shy. She told me she’d had sexual experiences with three girls. ‘I’m a pro at this, baby!’ she said.

"She said one affair – with a girl her age at school – was a serious lesbian relationship. The other two were more like sexual experimentation.

"She suddenly asked, ‘Do YOU want to try it?’

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