Serbia's Novak Djokovic has won the Australian Open six times — in 2008, 2011, 2012, 2013 and 2015, and then on Sunday. William West/AFP/Getty Images hide caption

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The BBC and BuzzFeed published an investigative report alleging widespread match-fixing and corruption in the sport of tennis. The report was released just before the start of the Australian Open. Rafiq Maqbool/AP hide caption

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Stanislas Wawrinka of Switzerland kisses the Australian Open trophy during the awarding ceremony after winning the men's singles final against Spain's Rafael Nadal on Sunday in Melbourne, Australia. Xu Yanyan/Xinhua/Landov hide caption

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Rafael Nadal of Spain celebrates after defeating Roger Federer of Switzerland during their semifinal Friday at the Australian Open tennis championship in Melbourne. Aaron Favila/AP hide caption

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