China won three of the four gold medals, but the United States and France were denied places on the top of the podium under a complicated tiebreak system never before used at the Olympics.

Chen Yibing emerged victorious for China in men's rings, He Kexin won on women's uneven bars and He Wenna claimed gold on women's trampoline, in a national gymnastics dominance unseen since the days of the Soviet Union.

The reigning champion on men's vault, Leszek Blanik of Poland, also added Olympic gold to his collection.

But the spotlight fell on the new gymnastics scoring system, under which the old "perfect 10" was replaced with two marks, one a mark out of 10 for execution and another reflecting the difficulty of the routine.

In the uneven bars final, He and US gymnast Nastia Liukin both scored 9.025 for execution and 7.7 for difficulty, to give each a final score of 16.725.

But instead of sharing gold, officials implemented a countback system where the highest and lowest of the five judges marks were progressively removed until a winner emerged.

"I don't know if anybody understands what the hell is going on," Liukin's father and coach Valeri said, pointing out that he tied and shared an Olympic gold on the high bar competing for the Soviet Union in the 1988 Seoul Games.

"I tied in my Olympic Games but I guess they don't want it now," he added.

His daughter, who won the women's individual gold medal last Friday, was also at a loss to explain the situation.

"I honestly was in shock," she said. "I knew I didn't have my best routine (but) when I saw we got the same score and my name was second, it was weird."

The same situation occurred in the men's vault final, when Blanik and France's Thomas Bouhail both scored 9.5375 for execution and 7.0 for difficulty for a total of 16.537. This time it was Bouhail who missed out on gold.

There was no scoring controvery involving Chen's victory on rings, where the reigning world champion on the apparatus was clearly dominant ahead of compatriot Yang Wei and Ukrainian Oleksandr Vorobiov.

"I felt coming first was normal, it was within my expectations," he said.

"If I tell you I wasn't nervous, that's impossible. To tell you the truth I couldn't sleep well and I felt like I was collapsing. I was going to bed at three and getting up at five."

On the uneven bars, China's Yang Yilin came third behind He and Liukin, with reigning world champion on the apparatus Ksenia Semenova finishing sixth.

Pole veteran Blanik's win on the vault was the first men's gymnastics event not won by China at the Beijing Games after no gymnasts from the home nation qualified for the final.

Blanik kissed a picture of his son after relegating Bouhail to silver and Anton Galotsuskov of Russia to bronze, saying he was looking forward to retirement.