Sweden's Sarah Sjostrom broke her own 100 metre butterfly world record after a stunning performance in the final on Sunday.
Sjostrom, also the reigning world champion, finished in 55.48 seconds to beat the previous record of 55.64 set in 2015, also becoming the first Swedish woman to ever win an Olympic gold medal in swimming.
The 22-year-old now has six of the top seven times in history of the event, an impressive feat considering her top four times have come outside of the now-banned supersuit era.
Canada's 16-year-old Penny Oleksiak took silver just under a second behind, followed by United States' Dana Vollmer.
Sjostrom was seeded first after Saturday's semi-finals by nearly a second after setting a then-Olympic record of 55.84, which was held by Vollmer at 55.98.
The Swede was favoured to win gold in London but failed to reach the podium altogether, finishing in fourth place in the final.
Sjostrom, who burst on the Olympic scene as a 14-year-old in the 2008 Beijing Games, is seeded first in the women's 200m freestyle ahead of American phenom Katie Ledecky.
She is also swimming in 50 and 100m freestyle as he looks to bring her medal count to four before the end of the Games.