 Complete the following phrase:  In 2015, he and Kim Sa-rang won the Korea Masters Grand Prix Gold tournament in the mens doubles event. In the final round they beat Ko Sung-hyun and Shin Baek-cheol with the score 16-21, 21-18, 21-19. They also won the China Open Super Series Premier tournament, after beat Chai Biao and Hong Wei in the straight games. 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. He and Kim Sa-rang competed at the Summer Olympics in the 