On May 5th, 2006, Canadian welterweight Chris Clements (1-1 at the time) met a first-time fighter named Lautaro Tucas at TKO 25 in Montreal. Putting his lack of experience on full display, Tucas opened the fight by skipping madly across the ring at Clements, his arms draped at his sides. Clements loaded up a right straight and immediately knocked Tucas out cold.

The stoppage was recorded at 0:03 of round 1 — the first three-second knockout in MMA history, establishing a record that has yet to be broken in professional competition. (In case you’re wondering, Kid Yamamoto’s famous flying knee was officially marked as four seconds, and the Harris/Fuller fake-tap backfire KO was recorded as five seconds, even though they both seemed to end just as immediately as Clements vs. Tucas.)

Tucas never fought again, but Clements — now 10-4 with all of his wins by KO/TKO — continued to compete in Canada, and is finally making his Octagon debut this Saturday at UFC 145 in Atlanta. Currently riding a four-fight win streak that includes stoppages of UFC vets Rich Clementi and Jonathan Goulet, Clements will be part of UFC 145′s Facebook prelims broadcast, facing off against Keith Wisniewski (28-13-1, 0-2 UFC), the Indiana-based journeyman who’s perhaps most famous for getting his arm snapped by Shinya Aoki.

After the jump: Two more examples of Clements’s freaky power.

#1: Chris Clements vs. Lautaro Tucas @ TKO 25 (5/5/06), 3 seconds

Just two days after Norifumi Yamamoto thrilled a Tokyo crowd with his four-second flying-knee KO against Kazuyuki Miyata, an eerily similar knockout took place in Montreal. Except this time, it was the dude sprinting across the ring who got himself KTFO — and in only three seconds, making this the fastest MMA knockout ever. We can only assume that Lautaro Tucas watched the Yamamoto/Miyata fight and thought, “Hey, I bet I could do that too.” But Chris Clements saw it coming, and stepped in with a sledgehammer right hook just as Tucas was leaving the ground. Tucas’s lifeless body flopped into the ropes, upon which Clements slugged him in the head three times. Awesome. Fun fact: Tucas never fought again after that night. We’re not sure if that’s because he switched to a less painful profession, or because he committed seppuku to make up for the shame he caused his family, but either way, it had to be done.

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