Emma Stone played tennis "every day for three months" in preparation for 'Battle of the Sexes'.
The 28-year-old actress portrays the 73-year-old professional tennis player in the production, which is based on the sportswoman's 1973 match against Bobby Riggs, and although the red head used to practice the sport as a child she was forced to train solidly with former tennis ace Vincent Spadea prior to picking up a racket in the upcoming movie.
Speaking to the Daily Mail newspaper, Emma said: "I was very much a novice. We played every day for three months, which was nothing compared to a lifetime for Billie Jean."
Emma also had sessions with Billie, who likened her movements on the court to dancing.
She said: "Billie Jean said: 'Your footwork is going to be great!' She'd throw the balls to me and I could move really quickly and she'd go: 'You move like a dancer!'
"We would do little pieces at a time and so they'd shout out my numbers and I'd go to the positions and do my forehand, or backhand."
But not only does the 'La La Land' star think her physical ability doesn't match the sporting legend, but she also thinks their appearances are very different too.
She explained: "The physicality was huge.
"Billie Jean has these big, incredible hands. Mine are tiny by comparison.
"She has this stance. Like a gladiator going into battle, ready to enter the ring. It was wonderful understanding what it would feel like to be in a body like that."
And Emma has revealed not only did she receive tips on how to serve from Billie, but she also learned that it is "ok to still be figuring" your life out.
She continued: "You can be confused about elements of your life. You can not necessarily be -- quote unquote -- 'fully formed'. I can definitely relate to this, because I have so much growing up to do.
"I learned from Billie Jean that it's OK to still be figuring it out. That's difficult for a perfectionist,' she says with a wry smile."
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