The Badminton World Federation has charged eight female Olympic doubles players with "not using one's best efforts to win a match".

Four pairs of players - two from South Korea, one from China and one from Indonesia - could be disciplined.

China's Yu Yang and Wang Xiaoli and South Koreans Jung Kyung-eun and Kim Ha-na are among those facing charges.

Both pairs were already through to the quarter-finals. Reports have suggested they both wanted to lose to secure an easier draw.

The unseeded South Koreans eventually won their match against China's Yu Yang and Wang Xiaoli on Tuesday, meaning they would next play China's Tian Qing and Zhao Yunlei.

The South Korean pair did not comment, but Yu said she and Wang were saving energy for the knockout stages.

China's Olympic sports delegation launched an investigation into the alleged "deliberate losing" by its badminton players, saying it opposed any behaviour violating "sporting spirit and morality", as reported by state media.

A later match between South Korean third seeds Ha Jung-Eun and Kim Min-Jung and Indonesian pair Meiliana Juahari and Greysia Polii is also under scrutiny by the Badminton World Federation.

Both pairs of those teams had also already qualified for the knockout stages, with the winner of Group C to play Yu and Wang and the Korean pairs to face each other if Ha and Kim lost.

At one point the referee, Berg, again intervened and brandished a black card to disqualify the players. However, he then rescinded his decision following protests from the two teams.

Both teams appeared keen to lose and therefore not play the Chinese in the next round, but the Koreans eventually won by two sets to one.

A statement from the BWF confirmed that all four pairs would face charges of "not using one's best efforts to win a match" and "conducting oneself in a manner that is clearly abusive or detrimental to the sport".

中文报道连接，

羽联指控8名运动员消极比赛 于洋王晓理或受罚,http://2012.sohu.com/20120801/n349572058.shtml