LONDON (Reuters) - Nathan Adrian claimed the title of the world's fastest man on water when he won the 100 metres freestyle gold medal by a fingernail at the London Olympics on Wednesday.
American teenager Missy Franklin then captured her second gold medal of the Games on a dramatic night of swimming that saw two world records broken and the host-nation make a rare appearance on the medal podium at the Aquatic Centre.
In a desperate finish to the 100 freestyle sprint, Adrian got his fingers on the wall ahead of Australian world champion James Magnussen by 0.01 seconds, the closest margin to a dead-heat in Olympic swimming.
It was impossible to split the pair with the naked eye but Adrian, the first American to win swimming's premier event in nearly a quarter of a century, was awarded the gold in a time of 47.52 seconds with Magnussen second in 47.53.
Canada's Brent Hayden was third in a classic race where the eight finalists were separated by less than a second.
"I almost started crying in the water. This is something that happens every four years," said Adrian, the first American to win the event since Matt Biondi in 1988.
"It's not who swims the fastest time this year but it's who can get their hands on the wall first here tonight."
Magnussen went into the Olympics as the favourite after winning the world title last year and boasting that he would win but said he had learnt a painful lesson.
"I just felt pretty much bullet proof coming into this Olympics and it is very humbling," he said.
"They say what doesn't kill you makes you stronger so hopefully I can come out of this a better swimmer but most of all a better person."
Franklin, her excitement already overflowing after she received a personal tweet from Canadian singer Justin Bieber, enhanced her status as the new queen of the pool when she teamed up with Dana Vollmer, Shannon Vreeland and Allison Schmitt to win the 4x200 freestyle relay, ahead of Australia and France.
The 17-year-old, appearing in her first Olympics, also won gold in the 100 backstroke and a bronze in the 4x100 freestyle relay and is not finished yet.
Less than an hour before the relay, she booked her place in the 100 freestyle final as the third fastest qualifier and still has her favourite event, the 200 backstroke, and the medley relay to come.
The U.S. have dominated the swimming events in London, winning medals in 17 of the 20 finals decided so far.
With three days to go the Americans have won eight golds and 18 medals in total.
China is second with four golds and medals in total after Jiao Liuyang stormed home on the last lap to win the women's 200 butterfly, four years after she finished second in Beijing.
Spain's Mireia Belmonte Garcia held on to take the silver after leading with one lap to go while Natsumi Hoshi of Japan was third.
Hungary's Daniel Gyurta broke the world record to win the 200 breaststroke final, denying the host-nation Britain their first male swimming champion since Adrian Moorehouse in Seoul.
Propelled by a deafening roar, Scotland's Michael Jamieson flashed home on the last length but could not quite reach Gyurta, who stopped the clock at 2:07.28 to shave 0.03 off the previous world record set by Australia's Christian Sprenger at the 2009 world championships in Rome.
"It was a really hard race. In the last 20 metres I saw Jamieson and the other British guy," Gyurta said.
"He was so fast the last 20 metres. It was really hard for me, but I did it."
Japan's Ryo Tateishi won the bronze ahead of compatriot Kosuke Kitajima, the two-time defending champion, bidding to become the first male swimmer to win the same event at three successive Olympics.
America's Rebecca Soni reclaimed her world record in the women's 200 breaststroke. The Beijing Olympic champion touched in 2:20.00 in her semi-final, wiping 0.12 off the previous mark set in Rome by Canada's Annamay Pierse.
(Editing by Greg Stutchbury)