After the film's release, the real Boris Becker said in an interview that he didn't enjoy it and didn't watch it until the end. He said "What should I say? Most of it didn't happen the way it was shown. And this is a shame." He said that he met the filmmakers a few times but at the end they didn't request any support from him. He added that Ion Tiriac was his strongest man and not Günther Bosch, as shown in the film. He added that he might make an own documentary someday and tell the story from his point of view.
In one earlier training scene Boris Becker is playing against a blonde girl named Steffi. It suppose to be the famous German tennis player Steffi Graf. She was 19 months younger and Becker had indeed to play against her and other girls as part of punishment for his bad tennis playing. In the late 80s Becker thanked Graf in a public letter for this and expressed his admiration.