Jake Gyllenhaal fancied Jennifer Aniston so much it was "torture" doing love scenes with the actress.
The pair starred together in 2002 film 'The Good Girl' and the 40-year-old star says it wasn't easy because of his real life crush on the 52-year-old 'Friends' actress.
Speaking during an interview with 'The Howard Stern Show', Jake was asked by the host if it was "torture" to film love scenes with somebody he fancied in real life.
Jake said: "Oh yeah, it was torture, yes it was.
"But it was also not torture.
"I mean, come on, it was like a mix of both."
But he said that such is the "mechanical nature" of love scenes he thankfully managed to keep his true feelings towards Jennifer well-hidden.
He added: "Weirdly, love scenes are awkward, because there are maybe 30, 50 people watching it?
"That doesn't turn me on.
"It's oddly mechanical.
"And also it's a dance, you're choreographing for a camera.
"You can get in it but it's like a fight scene, you have to choreograph those scenes."
And he added that a well-placed pillow, which was actually Jennifer's suggestion, helped.
He said: "The pillow technique was used.
"That was just preemptive and used generally always when actually in a horizontal place in that movie.
"I think that was actually a Jennifer suggestion, she was very kind to suggest it before we began.
"She was like, "I'm putting a pillow here.""
Meanwhile, Ben Stiller recently revealed how Jake nearly played Hansel in 'Zoolander'.
The 53-year-old actor - who played fictional male model Derek Zoolander in the 2001 cult classic comedy - admitted Owen Wilson almost missed out on his own supermodel role over doubts he'd be available to film.
Although Wilson was first choice, Stiller told Esquire: "The only one that I remember clearly was a young Jake Gyllenhaal doing this wide-eyed version of Hansel that was really funny."