If you have three seconds to spare, you can watch this knockout. At the Professional League of MMA event in Poland, Ivhan Bibiatov made quick of Mateusz Piechocki. If you're short on time, skip to the 1:30 mark for the start of the fight. If not, see how the introduction and the ring girl's saunter around the canvas takes longer than the actual fight.
Few things are as efficient as a swift kick to the face. The official time on the knockout is three seconds. The good news for Piechocki is that he was sitting up after that knockout.