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London-born KSI — real name Olajide "JJ" William Olatunji — pioneered YouTube celebrity boxing matches after making a name for himself playing FIFA on the platform. YouTube boxing matches are a hot new trend, kickstarted by KSI. Although the British vlogger first made his name playing video games on YouTube, he's pioneered boxing events as a way to whip up famous YouTubers' huge followings. The real-life matches could generate millions of pounds in ticket, merchandise, and streaming sales.