Kim Gi-jung

In 2008, he won a bronze medal at the World Junior Championships in the mixed doubles event partnered with Eom Hye-Won.^[3] In 2009, he competed at the Hong Kong East Asian Games and won a silver medal in the men's team event and a bronze medal in the men's doubles event partnered with Kwon Yi-goo.^[4] In 2011, he won the Turkey International tournament in the men's doubles event with Kim Sa-rang.^[5]

In 2012, he and Kim Sa-rang won their first Superseries title at the Japan Open tournament. In the final round they beat the Malaysian pair Koo Kien Keat and Tan Boon Heong.^[6] At the 2012 Badminton Asia Championships in Qingdao, China, they won a gold medal after defeat Hiroyuki Endo and Kenichi Hayakawa of Japan in the final round.^[7] In September 2012, they also won men's doubles title at the Indonesian Masters tournament.^[8]

In 2013, he became the champion at the Chinese Taipei and South Korea Grand Prix Gold tournament. At the Chinese Taipei, he and Kim Sa-rang beat the host partner Lee Sheng-mu and Tsai Chia-hsin in the straight set. At the Korea, they won the title after beat their compatriots Ko Sung-hyun and Shin Baek-cheol with the score 2–1.^[9][10] He also won a silver medal at the 2013 Badminton Asia Championships in Taipei.^[11] At the 2013 BWF World Championships in Guangzhou, he and his partner were seeded fifth in that tournament. They beat the second seeded of Malaysia in the quarterfinal round, and in the semifinal round they were defeated by Boe and Mogensen in three sets, and settle for the bronze medal.^[12] At the end of the 2013 BWF Season, he qualified to compete at the Super Series Masters Finals in Kuala Lumpur, Malaysia. Finally, he became the runner-up in the men's doubles event after defeated by Mohammad Ahsan and Hendra Setiawan of Indonesia.^[13]

In 2014, he and Lee Yong-dae have been handed one year suspensions for missing doping tests under the BWF Anti-Doping Regulations. He and Lee were required to provide whereabouts information for the BWF to conduct out-of-competition testing. In 2013, both athletes accumulated three whereabouts failures in connection with this administrative process.^[14] The Korea Badminton Association imposed $41,170 penalty for administrative failures. The panels that manage the doping tests reconsidered the case and decided to lift the punishment. The information and evidence presented at the January hearing was insufficient and ambiguous and there was no proof beyond reasonable doubt that the players were not at fault. In April 2014, after reviewing its original decision, the BWF panel wiped out the players missed tests and filing failures and expunged their records.^[15][16]

In 2015, he and Kim Sa-rang won the Korea Masters Grand Prix Gold tournament in the men's doubles event. In the final round they beat Ko Sung-hyun and Shin Baek-cheol with the score 16–21, 21–18, 21–19.^[17] They also won the China Open Super Series Premier tournament, after beat Chai Biao and Hong Wei in the straight games.^[18] In 2016, they also won the Superseries Premier tournament in Malaysia. He and Kim Sa-rang beat the third seeded from China in the quarterfinal round, and the world No.1 pair, Lee Yong-dae and Yoo Yeon-seong in the semifinal. In the final round they beat Chai Biao and Hong Wei with the score 21–19, 21–15.^[19] He and Kim Sa-rang competed at the Summer Olympics in the men's doubles event. They lost in the quarterfinal round, defeated by Fu Haifeng and Zhang Nan of China with the score 21–11, 18-21 and 22–24.^[20]