The International Olympic Committee has asked the national delegations of China, South Korea and Indonesia to investigate the role of their badminton coaches in a match-throwing scandal that led to the disqualification of eight players.

The Badminton World Federation will also review video of all round-robin matches at the tournament, a senior official told Reuters, after players and coaches slammed the pool round format for being ripe for manipulation.

The probes overshadowed day six of the competition, where players waged furious battles as they approached the medal rounds, in contrast to the farcical scenes in Tuesday's evening sessions where the four women's doubles pairs deliberately sprayed shots wide or into the net in the hope of losing.

"We want to see a positive result for the sport in the Olympics," IOC spokesman Mark Adams told reporters.

"And now we make sure they (the three national Olympic committees) also consider the entourage, to make sure it is not just the athletes who are punished for this.

"They are looking into this."

Adams said the eight disqualified women, including China's top-seeded pair of Yu Yang and Wang Xiaoli, were being removed from the athletes village and having their accreditations revoked.

China's head coach Li Yongbo has already admitted culpability for his players' losing tactics which were aimed at putting them into the opposite side of the draw from China's second-ranked doubles pair.

That would have prevented them from going head-to-head until the gold medal final.

Yu, who won the women's Olympic gold at Beijing with Du Jing, announced her retirement from the sport on her Chinese microblog and slammed the "heartless" Badminton World Federation (BWF) for shattering her and Wang's "dreams".

South Korea's head coach declined to comment on the fall-out from the scandal when questioned by Reuters.

With debate raging about the tournament's format, a senior BWF official said all round-robin matches at the London Olympics would be reviewed.

"Now we've obtained all the tapes. Right now we don't have so much time, but after the tournament is finished we will look to review everything, the whole situation," BWF deputy president Paisan Rangsikitpho said in an interview.

Rangsikitpho, the tournament's technical delegate, said the result of the review would not change the tournament's results but would help the BWF decide whether to persist with the controversial group format in the first round.

"I think the majority of the matches have been well received but I think something will be changed to ensure more fairness," he said.

China's remaining badminton players closed ranks at Wembley Arena as additional scrutiny was heaped upon the all-Chinese men's doubles match between world champions Cai Yu and Fu Haifeng and seventh-ranked pair Chai Biao and Guo Zhendong.

Cai and Fu won 21-15 21-19 over their compatriots with the near-packed house at the 4,800-seat Wembley Arena appreciating the match's intensity.

"We weren't affected by (the disqualifications). The controversy was for another team," said Cai, who won silver with Fu at the Beijing Games.

"We just wanted to do our best."