Budapest - Brazil's Etiene Medeiros won the women's 50m backstroke gold at the world championships on Thursday in a desperately tight final which she won on the wall.
Medeiros clocked 27.14 seconds, a new Americas record just 0.08 away from the world record set in 2009, while China's Fu Yuanhui took silver at 0.01 back.
Bulgaria's Aliaksandra Herasimenia earned bronze at just 0.09 behind as all eight swimmers in the final finished within half a second of Medeiros.
Having won silver at the Kazan world championships two years ago, the 26-year-old Medeiros went one better in Budapest having also come within 0.12 of the world record on Wednesday.
In the semi-finals, Fu had also been just 0.01 seconds behind Medeiros.
"I'm so happy. Two years ago I was second, but now I'm the champion, so this is so important in my life," said Medeiros.
"I want to thank to my coach - this year has been so different for me.
"Now I'm so relaxed.
"Last night was so hard for me, because I was thinking about the final.
"I wasn't confident of winning after last night's semi-finals and the Chinese was very strong today.
"I was a bit nervous, but I took time to relax and just be happy and it worked out."
Having been so narrowly beaten, Fu is edging her way towards her first major title.
"It was a very tight finish, but in backstroke, this is absolutely normal," said Fu.
"I'm not completely satisfied with my result, but, of course, I'm happy about my silver medal.
"Unfortunately, I couldn't swim my personal best, so I have a little feeling of wanting more."
Fu now has world silver after winning joint bronze over 100m at last year's Rio Olympics.
The video of the moment she was told she was on the podium in Rio went viral as Fu struggled to contain her emotions.
World swimming championship results on Thursday:
1. Chase Kalisz (USA) 1:55.56
2. Kosuke Hagino (JPN) 1:56.01
3. Wang Shun (CHN) 1:56.28
1. Caeleb Dressel (USA) 47.17
2. Nathan Adrian (USA) 47.87
3. Mehdy Metella (FRA) 47.89
1. Etiene Medeiros (BRA) 27.14
2. Fu Yuanhui (CHN) 27.15
3. Aliaksandra Herasimenia (BLR) 27.23
1. Mireia Belmonte (ESP) 2:05.26
2. Franziska Hentke (GER) 2:05.39
3. Katinka Hosszu (HUN) 2:06.02
4x200m freestyle relay
1. United States 7:43.39
2. China 7:44.96
3. Australia 7:48.51