LONDON -- Olympic officials demanded a deeper investigation into the badminton fixing scandal Thursday as China's coach took the blame for a match being thrown at the London Games and a player appeared to quit the tarnished sport.

The International Olympic Committee wants team coaches, trainers or officials of the four doubles pairs to be punished if they encouraged or ordered the eight now-disqualified players to lose intentionally.

The doubles teams -- the top-seeded pair from China, two pairs from South Korea and one from Indonesia -- were also set to have their accreditations removed by their national Olympic bodies and to be sent home.

Defending Olympic champion Yu Yang of China went further by apparently announcing her retirement from badminton.

"This is my last game," read a posting on a verified account for Yu on the Tencent microblogging service. "Farewell Badminton World Federation. Farewell my dear badminton."

Yu's retirement could not be immediately confirmed with Chinese badminton officials and was not referenced in an interview with state television.

"I think firstly we should apologize to the Chinese audience, because we did not demonstrate the Olympic spirit. We did not give the audience a game that fully demonstrated our skills," she said. "And it really resulted in a lot of negative influence."

Chinese badminton coach Li Yongbo also issued an apology, saying: "It's me to blame."

"We didn't take each competition seriously and follow the Olympic spirit of 'higher, faster and stronger' as professional athletes," Li added on Chinese television.

Yu and Wang Xiaoli, the world champions and Olympic gold-medal favorites, were one of four doubles teams that played poorly on purpose to secure a more favorable position in the quarterfinals lineup.

"I will prove myself in future games," Wang said. "I pledge to play to my full strength in future games, in each competition, to build a new image of us among the audience in the future."

Along with two teams from South Korea and another from Indonesia, it appeared to be the first mass disqualification in Olympic history.

The Chinese pair drew jeers as they intentionally lost to the South Koreans to rig the draw so they wouldn't have to face their second-seeded compatriots in the semifinals.

"We did not fully understand the significance of it," Li said. "As the head coach, I think I should, since the Badminton World Federation has already made the decision, apologize to the Chinese fans and audience, because, in fact, we didn't fully demonstrate the fighting spirit of the Chinese badminton team."