Salman Khan is busy with the shoot of his upcoming film, 'Sultan.' After much ado, the makers of the film have finally zeroed in on Anushka Sharma as the leading lady for the film. However, since the film is about wrestling, it requires the actors to fight it out. And in one of the fight sequences, Anushka had to slap Salman. While we have seen Anushka bash up the baddies in her production venture, 'NH10,' we don't think it will be a cakewalk for the actress to pull-off slapping Salman convincingly.