FUKUOKA -- Qin Haiyang earned his second breaststroke title first and then guided China to their first mixed 4x100m medley relay victory at the World Aquatics Championships on Wednesday.

The 24-year-old added the men's 50m breaststroke gold medal to his 100m triumph two days ago.

American Nic Fink, the defending champion, took silver and Qin's fellow Chinese Sun Jiajun finished third.

After about an hour's rest, Qin joined teammates Xu Jiayu, the 2017 and 2019 backstroke champion, Zhang Yufei, the 200m butterfly winner, and youngster Cheng Yujie to seal the relay title, beating Australia and the United States into second and third places.