Fournier is a professional boxer and is undefeated with a record of 9-0, lasting beating music artist Reykon in his last fight.
He also faced his pal David Haye in an exhibition fight, but KSI is also arguably his own toughest test.
KSI is 4-0 as a boxer and is ultimately gearing all his efforts toward a huge fight with Jake Paul at the end of the year.
A win over pro boxer Fournier, would give him a one-up over Paul, who failed in his quest to defeat Tommy Fury earlier this year.
When Is KSI vs Joe Fournier?
KSI takes on Fournier in a huge clash on Saturday, May 13.
The bout will be held at Wembley Arena in London.
Ring-walks for the main event can be expected around 10.30pm UK time.
The main card will get going from 7pm.
What has been said?
“Each fight, people are seeing a better KSI and I’m honestly scared for Fournier because once I land my right or left hand on his chin, it’s night night.
“As soon as people enter the ring with me, they realise they are in hell. And they either leave the ring bruised, battered or sleeping. In the ring, I am an evil man.”
“This is huge, it’s as big as it gets, it’s on DAZN pay-per-view at Wembley, against one of the biggest global superstars, not just in boxing.
“But I am going to break a lot of little hearts when they see KSI unconscious on the canvas.
“This is way too soon to fight me, but the deal is done, and just like Jake Paul, he will find out that when he gets into the ring with a real boxer, it’s a whole different ball game. He is in for a rude awakening.”
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