Matthew Semelsberger takes out opponent with 1 punch for 7th-fastest KO in UFC history

UFC Vegas 21 got off to a fast start. Literally.

Saturday's event headlined by Leon Edwards and Belal Muhammad opened with one of the shortest fights in UFC history, between Matt Semelsberger and Jason Witt. The bout was called after 16 seconds, in which Semelsberger landed a single counterpunch that sent Witt backward like he was doing a trust fall.

It was one of those magical little fights that can be tweeted out in their entirety:

That knockout win is the fastest the UFC has seen since Walt Harris knocked out Aleksei Oleinik in 15 seconds in July 2019, per ESPN's Marc Raimondi, and is the seventh-fastest knockout overall in the promotion's history.

The win improves Semelsberger's MMA record to 8-2. Saturday was only his second fight with UFC, and that KO is certainly a way to gain notice. A former second-team all-conference defensive back at Marist College, Semelsberger opened his pro MMA career in April 2017.

Semelsberger wasn't the end of wild KOs on Saturday, as featherweight Dan Ige delivered another counterpunch that put Gavin Tucker flat on his back hours later. Ige needed a full 23 seconds to pull that off.

And then there was Davey Grant doing this to Jonathan Martinez:

It's a violent sport, folks.

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