Five world records were shattered on an extraordinary night at the world short-course swimming championships on Friday.
Zimbabwe's Olympic champion Kirsty Coventry broke her second world record in three days, claiming her third title in the 200 metres backstroke as the world record tally soared to nine.
World marks were also set by Australian Felicity Galvez in the women's 50 butterfly, Croatia's Duje Draganja in the men's 50 freestyle, American Ryan Lochte in the 200 individual medley and the US in the women's 4x100 medley relay.
Coventry, who broke the 400 individual medley world mark on Wednesday, raced away in the 200 backstroke in two minutes 00.91 seconds, annihilating the 2:03.24 world mark set by Japan's Reiko Nakamura in Tokyo on Feb. 23 this year.
"I am tired. My legs (are) sore," said Coventry. "I'm very excited about that time. I'm excited I'm having a great meet."
Olympic silver medallist Draganja won in 20.81 seconds to beat the 20.93 world mark set by Stefan Nystrand of Sweden last November and retain his 50 freestyle crown ahead of Briton Mark Foster, bidding to become swimming's oldest world champion.
DRAGANJA CELEBRATES
"World records come and go. What matters is that I am the world record holder now," said Draganja. "I will celebrate tonight because tomorrow I might not have the record."
Foster, four times 50 freestyle gold medallist, had to settle for silver in 21.31 but said: "I'm not disappointed as I aimed for the stars and ended up on the moon, which isn't bad".
Lochte, who retained his 400 individual medley crown on Thursday, won an enthralling duel with newly-crowned 100 backstroke champion Liam Tancock of Britain.
The American triumphed in 1:51.56 to beat the 1:52.99 set by Laszlo Cseh of Hungary at the European short-course championships in Debrecen last December.
"It was a great race. I wouldn't have done it without these guys pushing me," said Lochte.
Galvez clocked 25.32 in the 50 butterfly to shave 0.01 seconds off Swede Anna-Karin Kammerling's 2005 mark.
"It still hasn't kind of set in," said Galvez. "I never believed I could set the world record, so it's a bit of a shock. I'm just so excited."
The U.S. won the medley relay in 3:51.36, beating the 3:51.84 set by Australia at the 2006 world short-course championships in Shanghai. Australia were second.
WAY INSIDE
US-based Coventry, who also won the 100 backstroke on Thursday, was way inside world record schedule all the way in the 200 backstroke and won by nearly two seconds.
Briton Lizzie Simmonds, who was also inside the old world mark in 2:02.60, was second with defending champion Margaret Hoelzer third.
However, Coventry was denied a fourth gold later in the evening when she finished third in the 100 individual medley behind victor Australian Shayne Reese.
Kylie Palmer, silver medallist in Thursday's 800 freestyle, struck gold in the women's 400 freestyle in 3:59.23 as Australia's women won three titles on the night.
Russia's Yuri Prilukov claimed his third successive world short-course 400 freestyle title, winning in 3:37.35 to add a silver to the bronze he took in Wednesday's 200 freestyle.
Marleen Veldhuis, who shared a world record in the Dutch women's 4x200 freestyle relay on Wednesday, got her second gold of the championships with a runaway win in the 100 freestyle.
Veldhuis, who won the 50 and 100 freestyle at last month's European long-course championships in Eindhoven, hurtled through the first 50 metres inside world record pace to win in 52.17.
Kris Gilchrist won the 200 breaststroke for hosts Britain in 2:06.18, just 0.03 seconds ahead of Thursday's 100 breaststroke winner Igor Borysik of Ukraine.