The long-anticipated boxing match between influencers Logan Paul and KSI had been hyped by YouTube as one of its biggest events of the year, but pay-per-view event was hijacked by pirated streams on Amazon's social video platform Twitch.
18,000 people bought tickets to watch the show in Manchester arena, and those watching from home were asked to stump up a $10 pay-per-view fee for match (around £7.50).
The match, which ended in a draw, had been touted as a testing bed for YouTube to see if it could monetise the fame of its high-profile creators on a pay-per-view basis. However, readily available pirtated broadcasts on the likes of Twtich and Twitter are reported to have drawn in a bigger audience than the official stream.
The Verge claims that the largest stream on Twitch had over 400,000 people on it and that "dozens of other unofficial broadcasts brought the overall tally up much higher".
The report also says one stream on Twitter-owned Periscope clocked up an audience of 70,000.
By comparison, the official YouTube stream is thought to have had around 773,000 viewers.
The Drum has reached out YouTube for clarification on the figures, at the time of writing the company hadn't responded.
Twitch says it's against its policy for streamers to upload content they don't have the rights to, saying it's been "responsive" to related reports.
YouTube had billed the fight as the "biggest event in internet history". It followed on from a previous boxing match the Google-owned video site hosted between KSI and Joe Weller in February which reached 1.8 million people via a free YouTube broadcast.
Paul and KSI have 37 million followers between them on YouTube. Paul has been the subject of controversy this year after publishing a video on the platform which showed the body of an apparent suicide victim in Japan.
YouTube's piracy dilemma will have given it a flavour of one of the biggest challenges sports broadcasters face.During this year's World Cup, anti-piracy firm VFT found 2,637 pirate streams of the semi finals on Facebook, YouTube and Periscope, with close to 30m views. It also identified 3,653 streams of the France-Croatia final, with more than 60 million views.