Around two months after his release from prison, Boris Becker described a documentary about the ups and downs of his life as a "matter of the heart" during the Berlinale on Sunday. "It was a privilege and a challenge to make the film," said the 55-year-old on Sunday in Berlin.

The first of two parts of Alex Gibney's production "Boom! Boom! The World vs. Boris Becker" was scheduled to premiere on Sunday at the International Film Festival.

"I'm a big fan of Boris," said Gibney. Making a film about him had another appeal: "He's also a storyteller who can tell his own story."

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