Beijing:Four world records tumbled in a remarkable second day of Olympic swimming on Monday as American superstar Michael Phelps' attempt to win an unprecedented eight gold medals stayed on track.
China proved too strong for the competition in men's synchronised diving and women's weightlifting.
Archery powerhouse South Korea took their gold tally to four with a men's team victory over Italy and the host nation, keeping them on course for a sweep of gold medals in the sport.
Out of competition, the first doping case of the Beijing Olympics saw Spanish cyclist Maria Isabel Moreno kicked out of the Games after testing positive for the blood booster EPO.
Phelps' hopes of eight golds stayed on course in the 4x100m relay thanks to a gigantic final effort from teammate Jason Lezak in the anchor leg.
His last-gasp touch enabled the Americans to beat France in a world record 3 minutes 8.24 seconds, slashing an astonishing 3.99 seconds off the world record they set in Sunday's semi-finals.
In an untypical burst of emotion, Phelps threw up his arms and cheered loudly with the rest of the team. "Jason in the last 50 metres was incredible. At the end, as you could see, I was pretty excited, I was very emotional," he said.
In the remarkable race, Australian opening swimmer Eamon Sullivan broke the 100m world record in a time of 47.24, France swam a European record 3:08.32 minutes and Australia took bronze with 3:09.91 as the top five teams were faster than the 15-hour-old former record from a US reserve team in the heats.
The two world records set in the relay brought the day's tally to four, with Zimbabwean Kirsty Coventry and Japan's Kosuke Kitajima providing the other two in the 100m breaststroke women's semis and men's final for seven records overall in the Beijing Water Cube.
First gold of the day went to Australian Lisbeth Trickett, who won the women's 100m butterfly in 56.73 seconds from Christine Magnuson of the US (57.10) and Jessicah Schipper of Australia (57.25), missing the eight-year-old world record of Dutch Inge de Bruijn by a mere 12 hundredths.
In the 100m breaststroke, Kitajima repeated his gold medal performance from Athens, winning in a world record time of 58.91 seconds, shaving 0.22 seconds off the previous mark of 59.13 seconds set by American Brendan Hansen two years ago.
Alexander Dale Oen gave Norway a first swim medal, a silver in 59.20, and Frenchman Hugues Duboscq took bronze in 59.37 seconds.
Briton Rebecca Adlington stunned American favourite Katie Hoff to win gold in the women's 400m freestyle in 4:03.22. Adlington was lying fourth at the last turn, but pulled out all the stops on the last lap to edge out her American rival by just 0.07.
In the women's 100m breaststroke semis, Coventry had 58.77 seconds to break the world record of 58.97 set by Natalie Coughlin at the US trials last month.
In women's trap shooting, Satu Makela-Nummela gave Finland its first gold, while silver medalist Zuzana Stefecekova broke Slovakia's Olympic duck. Bronze went to Corey Cogdell of the United States.
Defending Olympic champion Chen Yanqing retained her title in Women's 58 kg weightlifting with a total of 244kg to give the powerful Chinese lifting squad its third gold of the Games.
Russia's Marina Shainova lifted 129kg just six seconds before time ran out and took the silver medal with a total of 227kg. O Jong Ae of North Korea won bronze medal.
China remained on course a sweep of diving gold when world champions Lin Yue and Huo Liang won the men's 10 metres platform synchronized event. Germans Patrick Hausding and Sascha Klein took silver, with Russians Gleb Galperin and Dmitriy Dobroskok earning bronze.
It was meanwhile announced that Spanish cyclist Maria Isabel Moreno had been kicked out of the Games after she tested positive for the blood booster EPO, making her the first doping case in Beijing.
Moreno, 27, failed a test conducted on July 31 in the Olympic village and according to International Olympic Committee spokeswoman Giselle Davies flew home the same night before the test results were known. She was due to compete in the road time trial.