2008 UFC Knockouts
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Additionally, that same event saw a matchup between Keith Hackney and Joe Son in which Hackney unleashed a series of groin shots against Joe Son while on the ground.

UFC was similarly characterized, especially in the early days, as an extremely violent sport, as evidenced by a disclaimer in the beginning of the UFC 5 broadcast which warned audiences of the violent nature of the event.

A brief appearance of a match in the 1995 film Virtuosity likely did little to change this perception.