Blake Pieroni of the United States competes during Men's 200m Freestyle Final at 14th FINA World Swimming Championships (25m) in Hangzhou, East China's Zhejiang province, on Dec 12, 2018. Blake Pieroni claimed the title with 1:41.49. [Photo/Xinhua]

Cameron van der Burgh of South Africa celebrates after Men's 100m Breaststroke Final at 14th FINA World Swimming Championships (25m) in Hangzhou, East China's Zhejiang province, on Dec 12, 2018. Cameron van der Burgh claimed the title with 56.01 seconds. [Photo/Xinhua]

Katinka Hosszu of Hungary competes during Women's 200m Butterfly Final at 14th FINA World Swimming Championships (25m) in Hangzhou, East China's Zhejiang province, on Dec 12, 2018. Katinka Hosszu claimed the title with 2 minutes 1.60 seconds. [Photo/Xinhua]

Katinka Hosszu (L) of Hungary celebrates after Women's 200m Butterfly Final at 14th FINA World Swimming Championships (25m) in Hangzhou, East China's Zhejiang province, on Dec 12, 2018. Katinka Hosszu claimed the title with 2 minutes 1.60 seconds. [Photo/Xinhua]