Luke Wash, 17, of Gainesville, Florida, said he and the comedian were playing soccer before the brawl broke out.
He said Williams was ‘chilling on the field’ and then joined in the game, before throwing the punch.
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Luke Wash (right) beat up comedian Katt Williams after he claimed the 41-year-old sucker-punched him in the face
‘We were playing a game of soccer and I just thought it was a soccer game, but stuff happens in sports,’ Luke told DailyMail.com.
‘He took me over to a secluded area and asked me to hit him and I was like, “I’m not just going to hit you. You want to square up?”
‘And then he sucker-punched me so I did what I did,’ Luke said.
Luke, who said he was a wrestler for two years, has a swollen face but added that he wasn’t hurt.
‘I tried to shake his hand and he was like, “back off me little boy”.
‘I don’t know if he was sour but it is what it is,’ Luke said.
In the video of the fight, Luke jumped on Williams and put him in a headlock after he was punched in the face.
The beating was posted on the website Fameolous and on a Facebook page with a comment saying
‘He nothing but talk’.
The fight took place in Gainesville , Florida.
Police have reviewed the video and launched a criminal investigation into the incident, with Williams as the target, law enforcement officials told TMZ.
Williams is out on bail for multiple assault charges, and police are reviewing the bail order to determine if Williams violated his order. If he did, his bail could be revoked.
He was arrested earlier this month after a February 28 incident, in which the comedian allegedly threatened to kill Corey Dixon, his reported bodyguard.
The youngster got Williams into a choke-hold on the ground before a large crowd separated them.