American swimmer Michael Phelps became the most successful Olympian of all time by winning two more Beijing gold medals on Wednesday to take his career tally to an unprecedented 11 victories.
The mighty Phelps overtook an elite group including Mark Spitz and Carl Lewis who had won nine golds by breaking his own world record in the men's 200 metres butterfly.
Phelps brushed off a problem with his goggles that left them full of water. "Under the circumstances, it's not a bad result," he told reporters.
An hour later, the 23-year-old was back in the pool with his American team mates to win the men's 200 freestyle relay, knocking over four seconds off the previous world best. It was his fifth gold from these Games adding to six in Athens in 2004.
Phelps is now within reach of Spitz's record of seven golds at one Games. With each of his Beijing golds coming in record times he is also tracking Spitz's achievement of winning each of the 1972 titles in world best times.
The day's dry land highlight came when China took advantage of stumbles at key moments by the US to win one of the Games' showpiece events, the women's team artistic gymnastics.
Alicia Sacramone, the senior team member, stumbled off the beam after fluffing her mount and then fell flat on her back during her floor exercise. Shell-shocked at her disastrous mistakes, she hurried down the stairs and collapsed in tears.
It was the first victory in the event for the Chinese women.
An astonishing six world records were broken in the Water Cube pool, taking the tally for the Games to 16 in four days.
France's Alain Bernard briefly took Eamon Sullivan's world record in the 100 freestyle semi-finals but the Australian recaptured it less than five minutes later.
Italy's Federica Pellegrini broke the women's 200 freestyle record to take gold and ease the pain of losing in her favourite race, the 400 freestyle. Australia's Stephanie Rice won her second gold in record time in the 200 individual medley.
Phelps's triumphs pushed him ahead of Lewis, Spitz, "Flying Finn" distance runner Paavo Nurmi and Soviet gymnast Larysa Latynina on nine golds.
Latynina and fellow Soviet gymnast Nikolai Andrianov hold the record for the most career medals of any colour, with 18 for women and 15 for men.
China's determination to stage a successful Games has been criticised for going too far after organisers said they used a photogenic stand-in to lip-synch the voice of a less suitable looking 7-year-old girl singer at the opening ceremony.
Yang Peiyi's voice but not her face were used, "because of her external appearance," ceremony director Chen Qigang told state television. "It was for the national interest."
Opening ceremony fireworks were pre-recorded to make better television and empty seats are being filled with cheerleaders in other measures to give the Games a good gloss.
China and the United States are tussling for top place on the medals table with the Americans trailing the hosts 14 golds to 10, despite the Phelps phenomenon.
The Americans, who dethroned the Chinese as world champions in 2007, arrived with high hopes of winning their first women's Olympic gymnastics team title on foreign soil.
But a series of injuries left them only four fit gymnasts and their best hope was that the Chinese would fail to cope with an unaccustomed early start, after the event was switched to the morning to catch the prime-time American television market.
But China's women withstood the pressure to win in front of an ecstatic home crowd that expected nothing less than victory.
"Unfortunately we made two mistakes and you cannot win gold with two mistakes," said US team coordinator Martha Karolyi.
China's men had grabbed gold in their gymnastics team event on Tuesday, sparking national rejoicing after returning home from Athens in 2004 without a medal.
The women cyclists were thankful that Beijing's weather had improved for their 23.8km time trial between two sections of the Great Wall. It was won by American Kristin Armstrong.
Suffocating heat and smog forced a third of the field in the men's road race to quit the race on Saturday, while a day later thunderstorms and heavy rain left the women cyclists to face treacherously slippery conditions.
In a reminder of the struggle to keep the competition clean, two more possible doping incidents were revealed.
Bulgaria said it had sent home its men's volleyball captain after pre-Olympic doping controls showed he was close to anti-doping limits. Plamen Konstantinov would face further tests back home in Sofia, the volleyball federation said.
A Taiwanese baseball player tested positive for a banned substance in checks conducted before the Games started, the International Olympic Committee said. Jamaica said its athletes were being tested so heavily it could affect their performance.