Los Angeles - Cameron Diaz would have found her Bad Teacher sex scene awkward if it was with anyone other than Justin Timberlake.
The former couple - who dated for almost four years until December 2006 - star together in the comedy movie in which the actress' character Elizabeth Halsey romantically pursues Justin's alter-ego Scott Delacorte, and the blonde beauty admits she wouldn't have been so comfortable with anyone else.
She said: "If it was anyone else it would have been awkward. It would have been a different scene. But instead we laughed a lot. And because it was him, it just wasn't uncomfortable.
'Comfortable'
"We were able to do things I may not have been comfortable doing with somebody else. There is so much trust there, there is no issue.
"Justin and I know who we are and we know where we stand in our relationship. So there's a comfort in that and a safety."
Justin also recently insisted he didn't find shooting intimate scenes with his ex-girlfriend uncomfortable.
Asked if it was awkward because of their relationship history, Justin said: "I didn't look at it like that. We obviously know each other, but I looked at it as a really funny, funny scene that I've never seen done before.
"What I actually remember was, you know, they got to my close-up for that scene, so I was just kind of by myself - which is hard to imitate in real life."