Sometimes I confuse myself with these scans. There's two KO's here. The first one involves a girl named Rina Takaoka. She is knocked out with a powerful kick to the belly by some evil looking male student. The kick rips her school uniform to shreds. The guy is seen standing over her unconscious body.

Shortly after, Natsuki is shown knocking out a blonde haired girl via another belly punch. The blonde haired girl was an accomplice of the guy we saw earlier.