KSI got wiped out just 16 seconds into the Sidemen vs YouTube All Stars charity match.
Fellow YouTuber IShowSpeed sprinted across the pitch before clattering into KSI with a poorly timed challenge.
The American looked delighted with the tackle however, pounding the turf in celebration before jumping around with glee.
KSI could not help but laugh about the situation after his trash talk backfired in speculator fashion.
Ahead of the game KSI had mocked Speed's ability and wished for the streamer to have a terrible game.
KSI said: "My goal is to make sure Speed has a terrible time playing against me.
"This man is just pure trash, even against stinkers 😂😂. Man did one skill and was out of breath. Another fraud getting exposed this Saturday."
KSI was quick to laugh at himself and the incident with Speed after the full-time.
He tweeted: "Speed giving me an L in the first 20 seconds of the game too 😂."
Speed also made the most of the situation and started trolling KSI on social media.
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Sharing a photo of himself looking down on a floored KSI, Speed wrote: "I own you lil bro."
KSI had the last laugh however as his Sidemen team won 8-7 in front of a packed-out crowd at the Valley.
The event also attracted 2.5million concurrent viewers and raised more than £1m for charity.
