An American fighter scored a 16-second knockout Saturday, and it's the fastest finish in the UFC for 2 years

• Matthew Semelsberger scored a 16-second knockout win Saturday.
• The American said a kill-or-be-killed mentality may yield losses but it earned him a victory.
• Watch the quick-fire finish right here.

An American fighter called Matthew Semelsberger scored a 16-second knockout Saturday, and it's the fastest finish in the UFC for two years.

"I go into every fight with the kill or be killed, do or die attitude," Semelsberger, 28, told Insider in a statement after his win.

He added: "I'll be honest, I don't really think I'm going to win every single fight in the UFC but you will see me go for the kill, you will see me going to entertain people."

"Whether it's me lying unconscious or the other person lying unconscious, I'm going to throw everything that I got at them. That's probably why I'd say people enjoy watching me because I'm not afraid to risk it all."

That safety-averse attitude paid dividends at the behind-closed-doors UFC Fight Night 187 event inside the Apex in Las Vegas.

Semelsberger's welterweight fight against Jason Witt was the first match on the 13-bout card and there were barely any strikes thrown before it was all over.

Witt landed all four of his strike attempts before the finish, including a two-punch combo.

However, Semelsberger used half-steps to gradually close the gap on his opponent before pulling the trigger on a straight right hand, which landed on Witt's jaw so powerfully and accurately it put the fighter on the deck in an instant.

Semelsberger then pounced on his opponent to hit him with afters but could only land one before the referee intervened to call off the fight at the 16-second mark.

It is the fastest UFC finish since Walt Harris took 15 seconds to KO Aleksei Oleinik in July 2019, according to ESPN.

Watch the knockout right here:

With victory, Semelsberger advanced his pro MMA record eight wins (five knockouts, one submission, and two decisions) against two losses.

"I wasn't thinking about anything … kind of reacting off instinct, especially what my coaches were telling me to do and how I've been kind of preparing this whole week," he said in a statement sent to Insider.

"Don't think too much, all the work's been done, the cake's been baked, so I just went out there and did my thing."

"It's definitely rewarding," Semelsberger added. "Anybody who has worked really hard for something and they've gotten the desired result of it at that level of efficacy coming to fruition, it's nice. It feels really good."

He then said he'd like to fight at least one or two more times in 2021. "After the last fight I had the opportunity to come back quicker," he said, "but I didn't listen to my team and my family and everyone who told me to really just focus on the craft and get back in the gym. I'm going to do that as soon as I get home.

"Obviously, no injuries or anything like that, and hopefully get back in here as soon as possible."